Cleanup: Remove unimplemented UST domains
[lttng-tools.git] / src / bin / lttng-sessiond / main.c
CommitLineData
826d496d
MD
1/*
2 * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
0fdd1e2c 3 * Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
26296c48 4 * 2013 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
fac6795d 5 *
d14d33bf
AM
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License, version 2 only,
8 * as published by the Free Software Foundation.
91d76f53 9 *
d14d33bf
AM
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
91d76f53 14 *
d14d33bf
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15 * You should have received a copy of the GNU General Public License along
16 * with this program; if not, write to the Free Software Foundation, Inc.,
17 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
fac6795d
DG
18 */
19
20#define _GNU_SOURCE
6c1c0768 21#define _LGPL_SOURCE
fac6795d
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22#include <getopt.h>
23#include <grp.h>
24#include <limits.h>
0bb7724a 25#include <paths.h>
fac6795d
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26#include <pthread.h>
27#include <signal.h>
28#include <stdio.h>
29#include <stdlib.h>
30#include <string.h>
331744e3 31#include <inttypes.h>
0fdd1e2c 32#include <sys/mman.h>
b73401da 33#include <sys/mount.h>
1e307fab 34#include <sys/resource.h>
fac6795d
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35#include <sys/socket.h>
36#include <sys/stat.h>
37#include <sys/types.h>
0fdd1e2c 38#include <sys/wait.h>
5c827ce0 39#include <urcu/uatomic.h>
fac6795d 40#include <unistd.h>
3bd1e081 41#include <config.h>
fac6795d 42
990570ed 43#include <common/common.h>
d27c42b8 44#include <common/compat/socket.h>
e8fa9fb0 45#include <common/compat/getenv.h>
db758600
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46#include <common/defaults.h>
47#include <common/kernel-consumer/kernel-consumer.h>
50c8f484 48#include <common/futex.h>
00e2e675 49#include <common/relayd/relayd.h>
81b86775 50#include <common/utils.h>
3ccdf997 51#include <common/daemonize.h>
26296c48 52#include <common/config/config.h>
fac6795d 53
10a8a223 54#include "lttng-sessiond.h"
7972aab2 55#include "buffer-registry.h"
54d01ffb 56#include "channel.h"
2f77fc4b 57#include "cmd.h"
00e2e675 58#include "consumer.h"
099e26bd 59#include "context.h"
54d01ffb 60#include "event.h"
4771f025 61#include "kernel.h"
f1e16794 62#include "kernel-consumer.h"
096102bd 63#include "modprobe.h"
0fdd1e2c 64#include "shm.h"
1e307fab 65#include "ust-ctl.h"
00e2e675 66#include "ust-consumer.h"
8e68d1c8 67#include "utils.h"
4063050c 68#include "fd-limit.h"
8782cc74 69#include "health-sessiond.h"
8ac94142 70#include "testpoint.h"
d0b96690 71#include "ust-thread.h"
022d91ba 72#include "agent-thread.h"
fb198a11 73#include "save.h"
ef367a93 74#include "load-session-thread.h"
834978fd 75#include "syscall.h"
fac6795d 76
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MD
77#define CONSUMERD_FILE "lttng-consumerd"
78
fac6795d 79const char *progname;
6c71277b 80static const char *tracing_group_name = DEFAULT_TRACING_GROUP;
26296c48
JG
81static int tracing_group_name_override;
82static char *opt_pidfile;
5b8719f5 83static int opt_sig_parent;
97e19046 84static int opt_verbose_consumer;
72dd7491 85static int opt_daemon, opt_background;
4fba7219 86static int opt_no_kernel;
ef367a93 87static char *opt_load_session_path;
1d4b027a 88static pid_t ppid; /* Parent PID for --sig-parent option */
0bb7724a 89static pid_t child_ppid; /* Internal parent PID use with daemonize. */
67e40797 90static char *rundir;
c9cb3e7d 91static int lockfile_fd = -1;
3bd1e081 92
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93/* Set to 1 when a SIGUSR1 signal is received. */
94static int recv_child_signal;
95
a23ec3a7
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96/*
97 * Consumer daemon specific control data. Every value not initialized here is
98 * set to 0 by the static definition.
99 */
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100static struct consumer_data kconsumer_data = {
101 .type = LTTNG_CONSUMER_KERNEL,
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102 .err_unix_sock_path = DEFAULT_KCONSUMERD_ERR_SOCK_PATH,
103 .cmd_unix_sock_path = DEFAULT_KCONSUMERD_CMD_SOCK_PATH,
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104 .err_sock = -1,
105 .cmd_sock = -1,
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106 .pid_mutex = PTHREAD_MUTEX_INITIALIZER,
107 .lock = PTHREAD_MUTEX_INITIALIZER,
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108 .cond = PTHREAD_COND_INITIALIZER,
109 .cond_mutex = PTHREAD_MUTEX_INITIALIZER,
3bd1e081 110};
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MD
111static struct consumer_data ustconsumer64_data = {
112 .type = LTTNG_CONSUMER64_UST,
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113 .err_unix_sock_path = DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH,
114 .cmd_unix_sock_path = DEFAULT_USTCONSUMERD64_CMD_SOCK_PATH,
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MD
115 .err_sock = -1,
116 .cmd_sock = -1,
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117 .pid_mutex = PTHREAD_MUTEX_INITIALIZER,
118 .lock = PTHREAD_MUTEX_INITIALIZER,
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119 .cond = PTHREAD_COND_INITIALIZER,
120 .cond_mutex = PTHREAD_MUTEX_INITIALIZER,
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MD
121};
122static struct consumer_data ustconsumer32_data = {
123 .type = LTTNG_CONSUMER32_UST,
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124 .err_unix_sock_path = DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH,
125 .cmd_unix_sock_path = DEFAULT_USTCONSUMERD32_CMD_SOCK_PATH,
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MD
126 .err_sock = -1,
127 .cmd_sock = -1,
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128 .pid_mutex = PTHREAD_MUTEX_INITIALIZER,
129 .lock = PTHREAD_MUTEX_INITIALIZER,
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130 .cond = PTHREAD_COND_INITIALIZER,
131 .cond_mutex = PTHREAD_MUTEX_INITIALIZER,
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132};
133
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134/* Command line options */
135static const struct option long_options[] = {
136 { "client-sock", 1, 0, 'c' },
137 { "apps-sock", 1, 0, 'a' },
138 { "kconsumerd-cmd-sock", 1, 0, 'C' },
139 { "kconsumerd-err-sock", 1, 0, 'E' },
140 { "ustconsumerd32-cmd-sock", 1, 0, 'G' },
141 { "ustconsumerd32-err-sock", 1, 0, 'H' },
142 { "ustconsumerd64-cmd-sock", 1, 0, 'D' },
143 { "ustconsumerd64-err-sock", 1, 0, 'F' },
144 { "consumerd32-path", 1, 0, 'u' },
145 { "consumerd32-libdir", 1, 0, 'U' },
146 { "consumerd64-path", 1, 0, 't' },
147 { "consumerd64-libdir", 1, 0, 'T' },
148 { "daemonize", 0, 0, 'd' },
72dd7491 149 { "background", 0, 0, 'b' },
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150 { "sig-parent", 0, 0, 'S' },
151 { "help", 0, 0, 'h' },
152 { "group", 1, 0, 'g' },
153 { "version", 0, 0, 'V' },
154 { "quiet", 0, 0, 'q' },
155 { "verbose", 0, 0, 'v' },
156 { "verbose-consumer", 0, 0, 'Z' },
157 { "no-kernel", 0, 0, 'N' },
158 { "pidfile", 1, 0, 'p' },
1b2ef7fe 159 { "agent-tcp-port", 1, 0, 'J' },
26296c48 160 { "config", 1, 0, 'f' },
ef367a93 161 { "load", 1, 0, 'l' },
fbb9748b 162 { "kmod-probes", 1, 0, 'P' },
c9d42407 163 { "extra-kmod-probes", 1, 0, 'e' },
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164 { NULL, 0, 0, 0 }
165};
166
167/* Command line options to ignore from configuration file */
168static const char *config_ignore_options[] = { "help", "version", "config" };
169
26c9d55e 170/* Shared between threads */
099e26bd 171static int dispatch_thread_exit;
fac6795d 172
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173/* Global application Unix socket path */
174static char apps_unix_sock_path[PATH_MAX];
175/* Global client Unix socket path */
176static char client_unix_sock_path[PATH_MAX];
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177/* global wait shm path for UST */
178static char wait_shm_path[PATH_MAX];
44a5e5eb
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179/* Global health check unix path */
180static char health_unix_sock_path[PATH_MAX];
fac6795d 181
1d4b027a 182/* Sockets and FDs */
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183static int client_sock = -1;
184static int apps_sock = -1;
2f77fc4b 185int kernel_tracer_fd = -1;
76d7553f 186static int kernel_poll_pipe[2] = { -1, -1 };
1d4b027a 187
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188/*
189 * Quit pipe for all threads. This permits a single cancellation point
190 * for all threads when receiving an event on the pipe.
191 */
76d7553f 192static int thread_quit_pipe[2] = { -1, -1 };
4a15001e 193static int ht_cleanup_quit_pipe[2] = { -1, -1 };
273ea72c 194
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195/*
196 * This pipe is used to inform the thread managing application communication
197 * that a command is queued and ready to be processed.
198 */
76d7553f 199static int apps_cmd_pipe[2] = { -1, -1 };
099e26bd 200
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201int apps_cmd_notify_pipe[2] = { -1, -1 };
202
1d4b027a 203/* Pthread, Mutexes and Semaphores */
1d4b027a 204static pthread_t apps_thread;
d0b96690 205static pthread_t apps_notify_thread;
099e26bd 206static pthread_t reg_apps_thread;
1d4b027a 207static pthread_t client_thread;
7a485870 208static pthread_t kernel_thread;
099e26bd 209static pthread_t dispatch_thread;
44a5e5eb 210static pthread_t health_thread;
0b2dc8df 211static pthread_t ht_cleanup_thread;
022d91ba 212static pthread_t agent_reg_thread;
ef367a93 213static pthread_t load_session_thread;
5eb91c98 214
099e26bd
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215/*
216 * UST registration command queue. This queue is tied with a futex and uses a N
217 * wakers / 1 waiter implemented and detailed in futex.c/.h
218 *
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DG
219 * The thread_registration_apps and thread_dispatch_ust_registration uses this
220 * queue along with the wait/wake scheme. The thread_manage_apps receives down
221 * the line new application socket and monitors it for any I/O error or clean
222 * close that triggers an unregistration of the application.
099e26bd
DG
223 */
224static struct ust_cmd_queue ust_cmd_queue;
225
b5541356
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226/*
227 * Pointer initialized before thread creation.
228 *
229 * This points to the tracing session list containing the session count and a
230 * mutex lock. The lock MUST be taken if you iterate over the list. The lock
231 * MUST NOT be taken if you call a public function in session.c.
04ea676f 232 *
d063d709 233 * The lock is nested inside the structure: session_list_ptr->lock. Please use
54d01ffb 234 * session_lock_list and session_unlock_list for lock acquisition.
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235 */
236static struct ltt_session_list *session_list_ptr;
237
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MD
238int ust_consumerd64_fd = -1;
239int ust_consumerd32_fd = -1;
240
fb6f1fa2
YB
241static const char *consumerd32_bin = CONFIG_CONSUMERD32_BIN;
242static const char *consumerd64_bin = CONFIG_CONSUMERD64_BIN;
243static const char *consumerd32_libdir = CONFIG_CONSUMERD32_LIBDIR;
244static const char *consumerd64_libdir = CONFIG_CONSUMERD64_LIBDIR;
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245static int consumerd32_bin_override;
246static int consumerd64_bin_override;
247static int consumerd32_libdir_override;
248static int consumerd64_libdir_override;
fb09408a 249
2f77fc4b
DG
250static const char *module_proc_lttng = "/proc/lttng";
251
5c827ce0
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252/*
253 * Consumer daemon state which is changed when spawning it, killing it or in
254 * case of a fatal error.
255 */
256enum consumerd_state {
257 CONSUMER_STARTED = 1,
258 CONSUMER_STOPPED = 2,
259 CONSUMER_ERROR = 3,
260};
261
262/*
263 * This consumer daemon state is used to validate if a client command will be
264 * able to reach the consumer. If not, the client is informed. For instance,
265 * doing a "lttng start" when the consumer state is set to ERROR will return an
266 * error to the client.
267 *
268 * The following example shows a possible race condition of this scheme:
269 *
270 * consumer thread error happens
271 * client cmd arrives
272 * client cmd checks state -> still OK
273 * consumer thread exit, sets error
274 * client cmd try to talk to consumer
275 * ...
276 *
277 * However, since the consumer is a different daemon, we have no way of making
278 * sure the command will reach it safely even with this state flag. This is why
279 * we consider that up to the state validation during command processing, the
280 * command is safe. After that, we can not guarantee the correctness of the
281 * client request vis-a-vis the consumer.
282 */
283static enum consumerd_state ust_consumerd_state;
284static enum consumerd_state kernel_consumerd_state;
285
ae9e45b3
DG
286/*
287 * Socket timeout for receiving and sending in seconds.
288 */
289static int app_socket_timeout;
290
12744796
DG
291/* Set in main() with the current page size. */
292long page_size;
293
8782cc74
MD
294/* Application health monitoring */
295struct health_app *health_sessiond;
296
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297/* Agent TCP port for registration. Used by the agent thread. */
298unsigned int agent_tcp_port = DEFAULT_AGENT_TCP_PORT;
4d076222 299
f43f95a9
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300/* Am I root or not. */
301int is_root; /* Set to 1 if the daemon is running as root */
302
26296c48
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303const char * const config_section_name = "sessiond";
304
ef367a93
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305/* Load session thread information to operate. */
306struct load_session_thread_data *load_info;
307
97bc1426
MD
308/*
309 * Whether sessiond is ready for commands/health check requests.
310 * NR_LTTNG_SESSIOND_READY must match the number of calls to
ef367a93 311 * sessiond_notify_ready().
97bc1426 312 */
ef367a93 313#define NR_LTTNG_SESSIOND_READY 3
97bc1426
MD
314int lttng_sessiond_ready = NR_LTTNG_SESSIOND_READY;
315
316/* Notify parents that we are ready for cmd and health check */
ef367a93
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317LTTNG_HIDDEN
318void sessiond_notify_ready(void)
97bc1426
MD
319{
320 if (uatomic_sub_return(&lttng_sessiond_ready, 1) == 0) {
321 /*
322 * Notify parent pid that we are ready to accept command
323 * for client side. This ppid is the one from the
324 * external process that spawned us.
325 */
326 if (opt_sig_parent) {
327 kill(ppid, SIGUSR1);
328 }
329
330 /*
331 * Notify the parent of the fork() process that we are
332 * ready.
333 */
72dd7491 334 if (opt_daemon || opt_background) {
97bc1426
MD
335 kill(child_ppid, SIGUSR1);
336 }
337 }
338}
339
fb09408a 340static
7753dea8 341void setup_consumerd_path(void)
fb09408a 342{
fc7a59ce 343 const char *bin, *libdir;
fb09408a 344
7753dea8
MD
345 /*
346 * Allow INSTALL_BIN_PATH to be used as a target path for the
ebaeda94
MD
347 * native architecture size consumer if CONFIG_CONSUMER*_PATH
348 * has not been defined.
7753dea8 349 */
ebaeda94 350#if (CAA_BITS_PER_LONG == 32)
fc7a59ce
AM
351 if (!consumerd32_bin[0]) {
352 consumerd32_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
ebaeda94
MD
353 }
354 if (!consumerd32_libdir[0]) {
355 consumerd32_libdir = INSTALL_LIB_PATH;
356 }
357#elif (CAA_BITS_PER_LONG == 64)
fc7a59ce
AM
358 if (!consumerd64_bin[0]) {
359 consumerd64_bin = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
7753dea8 360 }
ebaeda94
MD
361 if (!consumerd64_libdir[0]) {
362 consumerd64_libdir = INSTALL_LIB_PATH;
7753dea8
MD
363 }
364#else
365#error "Unknown bitness"
366#endif
367
fb09408a
MD
368 /*
369 * runtime env. var. overrides the build default.
370 */
e8fa9fb0 371 bin = lttng_secure_getenv("LTTNG_CONSUMERD32_BIN");
fc7a59ce
AM
372 if (bin) {
373 consumerd32_bin = bin;
7753dea8 374 }
e8fa9fb0 375 bin = lttng_secure_getenv("LTTNG_CONSUMERD64_BIN");
fc7a59ce
AM
376 if (bin) {
377 consumerd64_bin = bin;
ebaeda94 378 }
e8fa9fb0 379 libdir = lttng_secure_getenv("LTTNG_CONSUMERD32_LIBDIR");
ebaeda94
MD
380 if (libdir) {
381 consumerd32_libdir = libdir;
382 }
e8fa9fb0 383 libdir = lttng_secure_getenv("LTTNG_CONSUMERD64_LIBDIR");
ebaeda94
MD
384 if (libdir) {
385 consumerd64_libdir = libdir;
fb09408a
MD
386 }
387}
388
4a15001e
MD
389static
390int __sessiond_set_thread_pollset(struct lttng_poll_event *events, size_t size,
391 int *a_pipe)
5eb91c98
DG
392{
393 int ret;
394
d0b96690 395 assert(events);
5eb91c98
DG
396
397 ret = lttng_poll_create(events, size, LTTNG_CLOEXEC);
398 if (ret < 0) {
399 goto error;
400 }
401
402 /* Add quit pipe */
4a15001e 403 ret = lttng_poll_add(events, a_pipe[0], LPOLLIN | LPOLLERR);
5eb91c98
DG
404 if (ret < 0) {
405 goto error;
406 }
407
408 return 0;
409
410error:
411 return ret;
412}
413
4a15001e
MD
414/*
415 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
416 */
417int sessiond_set_thread_pollset(struct lttng_poll_event *events, size_t size)
418{
419 return __sessiond_set_thread_pollset(events, size, thread_quit_pipe);
420}
421
422/*
423 * Create a poll set with O_CLOEXEC and add the thread quit pipe to the set.
424 */
425int sessiond_set_ht_cleanup_thread_pollset(struct lttng_poll_event *events,
426 size_t size)
427{
428 return __sessiond_set_thread_pollset(events, size,
429 ht_cleanup_quit_pipe);
430}
431
432static
433int __sessiond_check_thread_quit_pipe(int fd, uint32_t events, int a_pipe)
434{
435 if (fd == a_pipe && (events & LPOLLIN)) {
436 return 1;
437 }
438 return 0;
439}
440
5eb91c98
DG
441/*
442 * Check if the thread quit pipe was triggered.
443 *
444 * Return 1 if it was triggered else 0;
445 */
d0b96690 446int sessiond_check_thread_quit_pipe(int fd, uint32_t events)
5eb91c98 447{
4a15001e
MD
448 return __sessiond_check_thread_quit_pipe(fd, events,
449 thread_quit_pipe[0]);
450}
5eb91c98 451
4a15001e
MD
452/*
453 * Check if the ht_cleanup thread quit pipe was triggered.
454 *
455 * Return 1 if it was triggered else 0;
456 */
457int sessiond_check_ht_cleanup_quit(int fd, uint32_t events)
458{
459 return __sessiond_check_thread_quit_pipe(fd, events,
460 ht_cleanup_quit_pipe[0]);
5eb91c98
DG
461}
462
273ea72c 463/*
5eb91c98 464 * Init thread quit pipe.
273ea72c
DG
465 *
466 * Return -1 on error or 0 if all pipes are created.
467 */
4a15001e 468static int __init_thread_quit_pipe(int *a_pipe)
273ea72c 469{
730389d9 470 int ret, i;
273ea72c 471
4a15001e 472 ret = pipe(a_pipe);
273ea72c 473 if (ret < 0) {
730389d9 474 PERROR("thread quit pipe");
273ea72c
DG
475 goto error;
476 }
477
730389d9 478 for (i = 0; i < 2; i++) {
4a15001e 479 ret = fcntl(a_pipe[i], F_SETFD, FD_CLOEXEC);
730389d9
DG
480 if (ret < 0) {
481 PERROR("fcntl");
482 goto error;
483 }
484 }
485
273ea72c
DG
486error:
487 return ret;
488}
489
4a15001e
MD
490static int init_thread_quit_pipe(void)
491{
492 return __init_thread_quit_pipe(thread_quit_pipe);
493}
494
495static int init_ht_cleanup_quit_pipe(void)
496{
497 return __init_thread_quit_pipe(ht_cleanup_quit_pipe);
498}
499
099e26bd
DG
500/*
501 * Stop all threads by closing the thread quit pipe.
502 */
cf3af59e
MD
503static void stop_threads(void)
504{
5eb91c98
DG
505 int ret;
506
cf3af59e
MD
507 /* Stopping all threads */
508 DBG("Terminating all threads");
54d01ffb 509 ret = notify_thread_pipe(thread_quit_pipe[1]);
5eb91c98
DG
510 if (ret < 0) {
511 ERR("write error on thread quit pipe");
512 }
513
099e26bd 514 /* Dispatch thread */
26c9d55e 515 CMM_STORE_SHARED(dispatch_thread_exit, 1);
099e26bd 516 futex_nto1_wake(&ust_cmd_queue.futex);
cf3af59e
MD
517}
518
e975f9f8
DG
519/*
520 * Close every consumer sockets.
521 */
522static void close_consumer_sockets(void)
523{
524 int ret;
525
526 if (kconsumer_data.err_sock >= 0) {
527 ret = close(kconsumer_data.err_sock);
528 if (ret < 0) {
529 PERROR("kernel consumer err_sock close");
530 }
531 }
532 if (ustconsumer32_data.err_sock >= 0) {
533 ret = close(ustconsumer32_data.err_sock);
534 if (ret < 0) {
a76cbd9f 535 PERROR("UST consumerd32 err_sock close");
e975f9f8
DG
536 }
537 }
538 if (ustconsumer64_data.err_sock >= 0) {
539 ret = close(ustconsumer64_data.err_sock);
540 if (ret < 0) {
a76cbd9f 541 PERROR("UST consumerd64 err_sock close");
e975f9f8
DG
542 }
543 }
544 if (kconsumer_data.cmd_sock >= 0) {
545 ret = close(kconsumer_data.cmd_sock);
546 if (ret < 0) {
547 PERROR("kernel consumer cmd_sock close");
548 }
549 }
550 if (ustconsumer32_data.cmd_sock >= 0) {
551 ret = close(ustconsumer32_data.cmd_sock);
552 if (ret < 0) {
a76cbd9f 553 PERROR("UST consumerd32 cmd_sock close");
e975f9f8
DG
554 }
555 }
556 if (ustconsumer64_data.cmd_sock >= 0) {
557 ret = close(ustconsumer64_data.cmd_sock);
558 if (ret < 0) {
a76cbd9f 559 PERROR("UST consumerd64 cmd_sock close");
e975f9f8
DG
560 }
561 }
562}
563
c9cb3e7d
JG
564/*
565 * Generate the full lock file path using the rundir.
566 *
567 * Return the snprintf() return value thus a negative value is an error.
568 */
569static int generate_lock_file_path(char *path, size_t len)
570{
571 int ret;
572
573 assert(path);
574 assert(rundir);
575
576 /* Build lockfile path from rundir. */
577 ret = snprintf(path, len, "%s/" DEFAULT_LTTNG_SESSIOND_LOCKFILE, rundir);
578 if (ret < 0) {
579 PERROR("snprintf lockfile path");
580 }
581
582 return ret;
583}
584
fac6795d 585/*
4a15001e 586 * Cleanup the session daemon's data structures.
fac6795d 587 */
4a15001e 588static void sessiond_cleanup(void)
fac6795d 589{
ef599319 590 int ret;
af9737e9 591 struct ltt_session *sess, *stmp;
8c6c56c2 592 char path[PATH_MAX];
fac6795d 593
4a15001e 594 DBG("Cleanup sessiond");
e07ae692 595
4e449f3f
MD
596 /*
597 * Close the thread quit pipe. It has already done its job,
598 * since we are now called.
599 */
2f77fc4b
DG
600 utils_close_pipe(thread_quit_pipe);
601
35f90c40
DG
602 /*
603 * If opt_pidfile is undefined, the default file will be wiped when
604 * removing the rundir.
605 */
606 if (opt_pidfile) {
607 ret = remove(opt_pidfile);
608 if (ret < 0) {
609 PERROR("remove pidfile %s", opt_pidfile);
610 }
611 }
612
8c6c56c2
MD
613 DBG("Removing sessiond and consumerd content of directory %s", rundir);
614
615 /* sessiond */
616 snprintf(path, PATH_MAX,
617 "%s/%s",
618 rundir, DEFAULT_LTTNG_SESSIOND_PIDFILE);
619 DBG("Removing %s", path);
620 (void) unlink(path);
621
cd9290dd 622 snprintf(path, PATH_MAX, "%s/%s", rundir,
022d91ba 623 DEFAULT_LTTNG_SESSIOND_AGENTPORT_FILE);
cd9290dd
DG
624 DBG("Removing %s", path);
625 (void) unlink(path);
626
8c6c56c2
MD
627 /* kconsumerd */
628 snprintf(path, PATH_MAX,
629 DEFAULT_KCONSUMERD_ERR_SOCK_PATH,
630 rundir);
631 DBG("Removing %s", path);
632 (void) unlink(path);
633
634 snprintf(path, PATH_MAX,
635 DEFAULT_KCONSUMERD_PATH,
636 rundir);
637 DBG("Removing directory %s", path);
638 (void) rmdir(path);
639
640 /* ust consumerd 32 */
641 snprintf(path, PATH_MAX,
642 DEFAULT_USTCONSUMERD32_ERR_SOCK_PATH,
643 rundir);
644 DBG("Removing %s", path);
645 (void) unlink(path);
646
647 snprintf(path, PATH_MAX,
648 DEFAULT_USTCONSUMERD32_PATH,
649 rundir);
650 DBG("Removing directory %s", path);
651 (void) rmdir(path);
652
653 /* ust consumerd 64 */
654 snprintf(path, PATH_MAX,
655 DEFAULT_USTCONSUMERD64_ERR_SOCK_PATH,
656 rundir);
657 DBG("Removing %s", path);
658 (void) unlink(path);
659
660 snprintf(path, PATH_MAX,
661 DEFAULT_USTCONSUMERD64_PATH,
662 rundir);
663 DBG("Removing directory %s", path);
664 (void) rmdir(path);
5461b305 665
99bab54f 666 DBG("Cleaning up all sessions");
fac6795d 667
b5541356 668 /* Destroy session list mutex */
273ea72c
DG
669 if (session_list_ptr != NULL) {
670 pthread_mutex_destroy(&session_list_ptr->lock);
671
672 /* Cleanup ALL session */
54d01ffb
DG
673 cds_list_for_each_entry_safe(sess, stmp,
674 &session_list_ptr->head, list) {
2f77fc4b 675 cmd_destroy_session(sess, kernel_poll_pipe[1]);
273ea72c
DG
676 }
677 }
678
099e26bd 679 DBG("Closing all UST sockets");
56fff090 680 ust_app_clean_list();
7972aab2 681 buffer_reg_destroy_registries();
099e26bd 682
4fba7219
DG
683 if (is_root && !opt_no_kernel) {
684 DBG2("Closing kernel fd");
a4b35e07 685 if (kernel_tracer_fd >= 0) {
76d7553f
MD
686 ret = close(kernel_tracer_fd);
687 if (ret) {
688 PERROR("close");
689 }
a4b35e07 690 }
2f50c8a3 691 DBG("Unloading kernel modules");
096102bd 692 modprobe_remove_lttng_all();
834978fd 693 free(syscall_table);
2f50c8a3 694 }
2f77fc4b 695
e975f9f8
DG
696 close_consumer_sockets();
697
ef367a93
JG
698 if (load_info) {
699 load_session_destroy_data(load_info);
700 free(load_info);
701 }
702
c9cb3e7d
JG
703 /*
704 * Cleanup lock file by deleting it and finaly closing it which will
705 * release the file system lock.
706 */
707 if (lockfile_fd >= 0) {
708 char lockfile_path[PATH_MAX];
709
4a15001e
MD
710 ret = generate_lock_file_path(lockfile_path,
711 sizeof(lockfile_path));
c9cb3e7d
JG
712 if (ret > 0) {
713 ret = remove(lockfile_path);
714 if (ret < 0) {
715 PERROR("remove lock file");
716 }
717 ret = close(lockfile_fd);
718 if (ret < 0) {
719 PERROR("close lock file");
720 }
721 }
722 }
723
724 /*
725 * We do NOT rmdir rundir because there are other processes
726 * using it, for instance lttng-relayd, which can start in
727 * parallel with this teardown.
728 */
729
730 free(rundir);
4a15001e
MD
731}
732
733/*
734 * Cleanup the daemon's option data structures.
735 */
736static void sessiond_cleanup_options(void)
737{
738 DBG("Cleaning up options");
739
740 /*
741 * If the override option is set, the pointer points to a *non* const
742 * thus freeing it even though the variable type is set to const.
743 */
744 if (tracing_group_name_override) {
745 free((void *) tracing_group_name);
746 }
747 if (consumerd32_bin_override) {
748 free((void *) consumerd32_bin);
749 }
750 if (consumerd64_bin_override) {
751 free((void *) consumerd64_bin);
752 }
753 if (consumerd32_libdir_override) {
754 free((void *) consumerd32_libdir);
755 }
756 if (consumerd64_libdir_override) {
757 free((void *) consumerd64_libdir);
758 }
759
760 free(opt_pidfile);
761 free(opt_load_session_path);
762 free(kmod_probes_list);
763 free(kmod_extra_probes_list);
c9cb3e7d 764
421cb601 765 /* <fun> */
f56a39af 766 DBG("%c[%d;%dm*** assert failed :-) *** ==> %c[%dm%c[%d;%dm"
421cb601
DG
767 "Matthew, BEET driven development works!%c[%dm",
768 27, 1, 31, 27, 0, 27, 1, 33, 27, 0);
769 /* </fun> */
fac6795d
DG
770}
771
e065084a 772/*
d063d709 773 * Send data on a unix socket using the liblttsessiondcomm API.
e065084a 774 *
d063d709 775 * Return lttcomm error code.
e065084a
DG
776 */
777static int send_unix_sock(int sock, void *buf, size_t len)
778{
779 /* Check valid length */
c617c0c6 780 if (len == 0) {
e065084a
DG
781 return -1;
782 }
783
784 return lttcomm_send_unix_sock(sock, buf, len);
785}
786
5461b305 787/*
d063d709 788 * Free memory of a command context structure.
5461b305 789 */
a2fb29a5 790static void clean_command_ctx(struct command_ctx **cmd_ctx)
5461b305 791{
a2fb29a5
DG
792 DBG("Clean command context structure");
793 if (*cmd_ctx) {
794 if ((*cmd_ctx)->llm) {
795 free((*cmd_ctx)->llm);
5461b305 796 }
a2fb29a5
DG
797 if ((*cmd_ctx)->lsm) {
798 free((*cmd_ctx)->lsm);
5461b305 799 }
a2fb29a5
DG
800 free(*cmd_ctx);
801 *cmd_ctx = NULL;
5461b305
DG
802 }
803}
804
fac6795d 805/*
0fdd1e2c 806 * Notify UST applications using the shm mmap futex.
fac6795d 807 */
0fdd1e2c 808static int notify_ust_apps(int active)
fac6795d 809{
0fdd1e2c 810 char *wait_shm_mmap;
fac6795d 811
0fdd1e2c 812 DBG("Notifying applications of session daemon state: %d", active);
e07ae692 813
0fdd1e2c
DG
814 /* See shm.c for this call implying mmap, shm and futex calls */
815 wait_shm_mmap = shm_ust_get_mmap(wait_shm_path, is_root);
816 if (wait_shm_mmap == NULL) {
fac6795d
DG
817 goto error;
818 }
819
0fdd1e2c
DG
820 /* Wake waiting process */
821 futex_wait_update((int32_t *) wait_shm_mmap, active);
822
823 /* Apps notified successfully */
824 return 0;
fac6795d
DG
825
826error:
0fdd1e2c 827 return -1;
fac6795d
DG
828}
829
e065084a 830/*
d063d709
DG
831 * Setup the outgoing data buffer for the response (llm) by allocating the
832 * right amount of memory and copying the original information from the lsm
833 * structure.
ca95a216 834 *
d063d709 835 * Return total size of the buffer pointed by buf.
ca95a216 836 */
5461b305 837static int setup_lttng_msg(struct command_ctx *cmd_ctx, size_t size)
ca95a216 838{
f3ed775e 839 int ret, buf_size;
ca95a216 840
f3ed775e 841 buf_size = size;
5461b305 842
ba7f0ae5 843 cmd_ctx->llm = zmalloc(sizeof(struct lttcomm_lttng_msg) + buf_size);
5461b305 844 if (cmd_ctx->llm == NULL) {
76d7553f 845 PERROR("zmalloc");
5461b305 846 ret = -ENOMEM;
ca95a216
DG
847 goto error;
848 }
849
5461b305
DG
850 /* Copy common data */
851 cmd_ctx->llm->cmd_type = cmd_ctx->lsm->cmd_type;
9f19cc17 852 cmd_ctx->llm->pid = cmd_ctx->lsm->domain.attr.pid;
5461b305 853
5461b305
DG
854 cmd_ctx->llm->data_size = size;
855 cmd_ctx->lttng_msg_size = sizeof(struct lttcomm_lttng_msg) + buf_size;
856
ca95a216
DG
857 return buf_size;
858
859error:
860 return ret;
861}
862
7a485870 863/*
5eb91c98 864 * Update the kernel poll set of all channel fd available over all tracing
d063d709 865 * session. Add the wakeup pipe at the end of the set.
7a485870 866 */
5eb91c98 867static int update_kernel_poll(struct lttng_poll_event *events)
7a485870 868{
5eb91c98 869 int ret;
7a485870
DG
870 struct ltt_session *session;
871 struct ltt_kernel_channel *channel;
872
5eb91c98 873 DBG("Updating kernel poll set");
7a485870 874
54d01ffb 875 session_lock_list();
b5541356 876 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
54d01ffb 877 session_lock(session);
7a485870 878 if (session->kernel_session == NULL) {
54d01ffb 879 session_unlock(session);
7a485870
DG
880 continue;
881 }
7a485870 882
54d01ffb
DG
883 cds_list_for_each_entry(channel,
884 &session->kernel_session->channel_list.head, list) {
5eb91c98
DG
885 /* Add channel fd to the kernel poll set */
886 ret = lttng_poll_add(events, channel->fd, LPOLLIN | LPOLLRDNORM);
887 if (ret < 0) {
54d01ffb 888 session_unlock(session);
5eb91c98
DG
889 goto error;
890 }
891 DBG("Channel fd %d added to kernel set", channel->fd);
7a485870 892 }
54d01ffb 893 session_unlock(session);
7a485870 894 }
54d01ffb 895 session_unlock_list();
7a485870 896
5eb91c98 897 return 0;
7a485870
DG
898
899error:
54d01ffb 900 session_unlock_list();
7a485870
DG
901 return -1;
902}
903
904/*
54d01ffb 905 * Find the channel fd from 'fd' over all tracing session. When found, check
d063d709 906 * for new channel stream and send those stream fds to the kernel consumer.
7a485870 907 *
d063d709 908 * Useful for CPU hotplug feature.
7a485870 909 */
2bdd86d4 910static int update_kernel_stream(struct consumer_data *consumer_data, int fd)
7a485870
DG
911{
912 int ret = 0;
913 struct ltt_session *session;
173af62f 914 struct ltt_kernel_session *ksess;
7a485870
DG
915 struct ltt_kernel_channel *channel;
916
917 DBG("Updating kernel streams for channel fd %d", fd);
918
54d01ffb 919 session_lock_list();
b5541356 920 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
54d01ffb 921 session_lock(session);
7a485870 922 if (session->kernel_session == NULL) {
54d01ffb 923 session_unlock(session);
7a485870
DG
924 continue;
925 }
173af62f 926 ksess = session->kernel_session;
d9800920 927
4a15001e
MD
928 cds_list_for_each_entry(channel,
929 &ksess->channel_list.head, list) {
930 struct lttng_ht_iter iter;
931 struct consumer_socket *socket;
d9800920 932
4a15001e
MD
933 if (channel->fd != fd) {
934 continue;
935 }
936 DBG("Channel found, updating kernel streams");
937 ret = kernel_open_channel_stream(channel);
938 if (ret < 0) {
939 goto error;
940 }
941 /* Update the stream global counter */
942 ksess->stream_count_global += ret;
943
944 /*
945 * Have we already sent fds to the consumer? If yes, it
946 * means that tracing is started so it is safe to send
947 * our updated stream fds.
948 */
949 if (ksess->consumer_fds_sent != 1
950 || ksess->consumer == NULL) {
951 ret = -1;
952 goto error;
953 }
954
955 rcu_read_lock();
956 cds_lfht_for_each_entry(ksess->consumer->socks->ht,
957 &iter.iter, socket, node.node) {
958 pthread_mutex_lock(socket->lock);
959 ret = kernel_consumer_send_channel_stream(socket,
960 channel, ksess,
961 session->output_traces ? 1 : 0);
962 pthread_mutex_unlock(socket->lock);
963 if (ret < 0) {
e7fe706f 964 rcu_read_unlock();
4a15001e 965 goto error;
7a485870 966 }
7a485870 967 }
4a15001e 968 rcu_read_unlock();
7a485870 969 }
54d01ffb 970 session_unlock(session);
7a485870 971 }
54d01ffb 972 session_unlock_list();
b3c750d2 973 return ret;
7a485870 974
b3c750d2 975error:
54d01ffb
DG
976 session_unlock(session);
977 session_unlock_list();
7a485870
DG
978 return ret;
979}
980
487cf67c 981/*
ffe60014
DG
982 * For each tracing session, update newly registered apps. The session list
983 * lock MUST be acquired before calling this.
487cf67c
DG
984 */
985static void update_ust_app(int app_sock)
986{
987 struct ltt_session *sess, *stmp;
988
fdadac08
DG
989 /* Consumer is in an ERROR state. Stop any application update. */
990 if (uatomic_read(&ust_consumerd_state) == CONSUMER_ERROR) {
991 /* Stop the update process since the consumer is dead. */
992 return;
993 }
994
487cf67c
DG
995 /* For all tracing session(s) */
996 cds_list_for_each_entry_safe(sess, stmp, &session_list_ptr->head, list) {
4ee14516 997 session_lock(sess);
421cb601
DG
998 if (sess->ust_session) {
999 ust_app_global_update(sess->ust_session, app_sock);
1000 }
4ee14516 1001 session_unlock(sess);
487cf67c
DG
1002 }
1003}
1004
7a485870 1005/*
d063d709 1006 * This thread manage event coming from the kernel.
7a485870 1007 *
d063d709
DG
1008 * Features supported in this thread:
1009 * -) CPU Hotplug
7a485870
DG
1010 */
1011static void *thread_manage_kernel(void *data)
1012{
139ac872 1013 int ret, i, pollfd, update_poll_flag = 1, err = -1;
5eb91c98 1014 uint32_t revents, nb_fd;
7a485870 1015 char tmp;
5eb91c98 1016 struct lttng_poll_event events;
7a485870 1017
6993eeb3 1018 DBG("[thread] Thread manage kernel started");
7a485870 1019
6c71277b 1020 health_register(health_sessiond, HEALTH_SESSIOND_TYPE_KERNEL);
927ca06a 1021
d5d63bf1
DG
1022 /*
1023 * This first step of the while is to clean this structure which could free
6d737ce4 1024 * non NULL pointers so initialize it before the loop.
d5d63bf1 1025 */
6d737ce4 1026 lttng_poll_init(&events);
d5d63bf1 1027
e547b070 1028 if (testpoint(sessiond_thread_manage_kernel)) {
6993eeb3
CB
1029 goto error_testpoint;
1030 }
8ac94142 1031
840cb59c 1032 health_code_update();
44a5e5eb 1033
e547b070 1034 if (testpoint(sessiond_thread_manage_kernel_before_loop)) {
d21b0d71 1035 goto error_testpoint;
6993eeb3
CB
1036 }
1037
7a485870 1038 while (1) {
840cb59c 1039 health_code_update();
44a5e5eb 1040
7a485870 1041 if (update_poll_flag == 1) {
d21b0d71
DG
1042 /* Clean events object. We are about to populate it again. */
1043 lttng_poll_clean(&events);
1044
d0b96690 1045 ret = sessiond_set_thread_pollset(&events, 2);
d21b0d71
DG
1046 if (ret < 0) {
1047 goto error_poll_create;
1048 }
1049
1050 ret = lttng_poll_add(&events, kernel_poll_pipe[0], LPOLLIN);
1051 if (ret < 0) {
1052 goto error;
1053 }
5f822d0a 1054
d21b0d71 1055 /* This will add the available kernel channel if any. */
5eb91c98
DG
1056 ret = update_kernel_poll(&events);
1057 if (ret < 0) {
7a485870
DG
1058 goto error;
1059 }
1060 update_poll_flag = 0;
1061 }
1062
7fa2082e 1063 DBG("Thread kernel polling");
7a485870
DG
1064
1065 /* Poll infinite value of time */
88f2b785 1066 restart:
a78af745 1067 health_poll_entry();
5eb91c98 1068 ret = lttng_poll_wait(&events, -1);
7fa2082e
MD
1069 DBG("Thread kernel return from poll on %d fds",
1070 LTTNG_POLL_GETNB(&events));
a78af745 1071 health_poll_exit();
7a485870 1072 if (ret < 0) {
88f2b785
MD
1073 /*
1074 * Restart interrupted system call.
1075 */
1076 if (errno == EINTR) {
1077 goto restart;
1078 }
7a485870
DG
1079 goto error;
1080 } else if (ret == 0) {
1081 /* Should not happen since timeout is infinite */
85611738
DG
1082 ERR("Return value of poll is 0 with an infinite timeout.\n"
1083 "This should not have happened! Continuing...");
7a485870
DG
1084 continue;
1085 }
1086
0d9c5d77
DG
1087 nb_fd = ret;
1088
5eb91c98
DG
1089 for (i = 0; i < nb_fd; i++) {
1090 /* Fetch once the poll data */
1091 revents = LTTNG_POLL_GETEV(&events, i);
1092 pollfd = LTTNG_POLL_GETFD(&events, i);
7a485870 1093
840cb59c 1094 health_code_update();
44a5e5eb 1095
fd20dac9
MD
1096 if (!revents) {
1097 /* No activity for this FD (poll implementation). */
1098 continue;
1099 }
1100
5eb91c98 1101 /* Thread quit pipe has been closed. Killing thread. */
d0b96690 1102 ret = sessiond_check_thread_quit_pipe(pollfd, revents);
5eb91c98 1103 if (ret) {
139ac872
MD
1104 err = 0;
1105 goto exit;
5eb91c98 1106 }
7a485870 1107
5eb91c98
DG
1108 /* Check for data on kernel pipe */
1109 if (pollfd == kernel_poll_pipe[0] && (revents & LPOLLIN)) {
6cd525e8
MD
1110 (void) lttng_read(kernel_poll_pipe[0],
1111 &tmp, 1);
f921c78f
DG
1112 /*
1113 * Ret value is useless here, if this pipe gets any actions an
1114 * update is required anyway.
1115 */
5eb91c98
DG
1116 update_poll_flag = 1;
1117 continue;
1118 } else {
1119 /*
1120 * New CPU detected by the kernel. Adding kernel stream to
1121 * kernel session and updating the kernel consumer
1122 */
1123 if (revents & LPOLLIN) {
2bdd86d4 1124 ret = update_kernel_stream(&kconsumer_data, pollfd);
5eb91c98
DG
1125 if (ret < 0) {
1126 continue;
1127 }
1128 break;
1129 /*
1130 * TODO: We might want to handle the LPOLLERR | LPOLLHUP
1131 * and unregister kernel stream at this point.
1132 */
7a485870 1133 }
7a485870
DG
1134 }
1135 }
1136 }
1137
139ac872 1138exit:
7a485870 1139error:
5eb91c98 1140 lttng_poll_clean(&events);
76d7553f 1141error_poll_create:
6993eeb3 1142error_testpoint:
6620da75
DG
1143 utils_close_pipe(kernel_poll_pipe);
1144 kernel_poll_pipe[0] = kernel_poll_pipe[1] = -1;
139ac872 1145 if (err) {
840cb59c 1146 health_error();
139ac872 1147 ERR("Health error occurred in %s", __func__);
6620da75
DG
1148 WARN("Kernel thread died unexpectedly. "
1149 "Kernel tracing can continue but CPU hotplug is disabled.");
139ac872 1150 }
8782cc74 1151 health_unregister(health_sessiond);
76d7553f 1152 DBG("Kernel thread dying");
7a485870
DG
1153 return NULL;
1154}
1155
a23ec3a7
DG
1156/*
1157 * Signal pthread condition of the consumer data that the thread.
1158 */
1159static void signal_consumer_condition(struct consumer_data *data, int state)
1160{
1161 pthread_mutex_lock(&data->cond_mutex);
1162
1163 /*
1164 * The state is set before signaling. It can be any value, it's the waiter
1165 * job to correctly interpret this condition variable associated to the
1166 * consumer pthread_cond.
1167 *
1168 * A value of 0 means that the corresponding thread of the consumer data
1169 * was not started. 1 indicates that the thread has started and is ready
1170 * for action. A negative value means that there was an error during the
1171 * thread bootstrap.
1172 */
1173 data->consumer_thread_is_ready = state;
1174 (void) pthread_cond_signal(&data->cond);
1175
1176 pthread_mutex_unlock(&data->cond_mutex);
1177}
1178
1d4b027a 1179/*
3bd1e081 1180 * This thread manage the consumer error sent back to the session daemon.
1d4b027a 1181 */
3bd1e081 1182static void *thread_manage_consumer(void *data)
1d4b027a 1183{
42fc1d0b 1184 int sock = -1, i, ret, pollfd, err = -1, should_quit = 0;
5eb91c98 1185 uint32_t revents, nb_fd;
1d4b027a 1186 enum lttcomm_return_code code;
5eb91c98 1187 struct lttng_poll_event events;
3bd1e081 1188 struct consumer_data *consumer_data = data;
1d4b027a 1189
3bd1e081 1190 DBG("[thread] Manage consumer started");
1d4b027a 1191
6c71277b 1192 health_register(health_sessiond, HEALTH_SESSIOND_TYPE_CONSUMER);
927ca06a 1193
855060f8 1194 health_code_update();
9449cc75 1195
5eb91c98 1196 /*
331744e3
JD
1197 * Pass 3 as size here for the thread quit pipe, consumerd_err_sock and the
1198 * metadata_sock. Nothing more will be added to this poll set.
5eb91c98 1199 */
331744e3 1200 ret = sessiond_set_thread_pollset(&events, 3);
5eb91c98 1201 if (ret < 0) {
76d7553f 1202 goto error_poll;
5eb91c98 1203 }
273ea72c 1204
edb8b045
DG
1205 /*
1206 * The error socket here is already in a listening state which was done
1207 * just before spawning this thread to avoid a race between the consumer
1208 * daemon exec trying to connect and the listen() call.
1209 */
3bd1e081 1210 ret = lttng_poll_add(&events, consumer_data->err_sock, LPOLLIN | LPOLLRDHUP);
5eb91c98
DG
1211 if (ret < 0) {
1212 goto error;
1213 }
1214
840cb59c 1215 health_code_update();
44a5e5eb 1216
331744e3 1217 /* Infinite blocking call, waiting for transmission */
88f2b785 1218restart:
a78af745 1219 health_poll_entry();
8ac94142 1220
e547b070 1221 if (testpoint(sessiond_thread_manage_consumer)) {
6993eeb3
CB
1222 goto error;
1223 }
8ac94142 1224
5eb91c98 1225 ret = lttng_poll_wait(&events, -1);
a78af745 1226 health_poll_exit();
273ea72c 1227 if (ret < 0) {
88f2b785
MD
1228 /*
1229 * Restart interrupted system call.
1230 */
1231 if (errno == EINTR) {
1232 goto restart;
1233 }
273ea72c
DG
1234 goto error;
1235 }
1236
0d9c5d77
DG
1237 nb_fd = ret;
1238
5eb91c98
DG
1239 for (i = 0; i < nb_fd; i++) {
1240 /* Fetch once the poll data */
1241 revents = LTTNG_POLL_GETEV(&events, i);
1242 pollfd = LTTNG_POLL_GETFD(&events, i);
1243
840cb59c 1244 health_code_update();
44a5e5eb 1245
fd20dac9
MD
1246 if (!revents) {
1247 /* No activity for this FD (poll implementation). */
1248 continue;
1249 }
1250
5eb91c98 1251 /* Thread quit pipe has been closed. Killing thread. */
d0b96690 1252 ret = sessiond_check_thread_quit_pipe(pollfd, revents);
5eb91c98 1253 if (ret) {
139ac872
MD
1254 err = 0;
1255 goto exit;
5eb91c98
DG
1256 }
1257
1258 /* Event on the registration socket */
3bd1e081 1259 if (pollfd == consumer_data->err_sock) {
5eb91c98 1260 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
3bd1e081 1261 ERR("consumer err socket poll error");
5eb91c98
DG
1262 goto error;
1263 }
1264 }
273ea72c
DG
1265 }
1266
3bd1e081 1267 sock = lttcomm_accept_unix_sock(consumer_data->err_sock);
1d4b027a
DG
1268 if (sock < 0) {
1269 goto error;
1270 }
1271
b662582b
DG
1272 /*
1273 * Set the CLOEXEC flag. Return code is useless because either way, the
1274 * show must go on.
1275 */
1276 (void) utils_set_fd_cloexec(sock);
1277
840cb59c 1278 health_code_update();
44a5e5eb 1279
3bd1e081 1280 DBG2("Receiving code from consumer err_sock");
ee0b0061 1281
712ea556 1282 /* Getting status code from kconsumerd */
54d01ffb
DG
1283 ret = lttcomm_recv_unix_sock(sock, &code,
1284 sizeof(enum lttcomm_return_code));
1d4b027a
DG
1285 if (ret <= 0) {
1286 goto error;
1287 }
1288
840cb59c 1289 health_code_update();
f73fabfd 1290 if (code == LTTCOMM_CONSUMERD_COMMAND_SOCK_READY) {
331744e3 1291 /* Connect both socket, command and metadata. */
3bd1e081
MD
1292 consumer_data->cmd_sock =
1293 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
4ce514c4 1294 consumer_data->metadata_fd =
331744e3 1295 lttcomm_connect_unix_sock(consumer_data->cmd_unix_sock_path);
92db7cdc
DG
1296 if (consumer_data->cmd_sock < 0
1297 || consumer_data->metadata_fd < 0) {
331744e3 1298 PERROR("consumer connect cmd socket");
a23ec3a7
DG
1299 /* On error, signal condition and quit. */
1300 signal_consumer_condition(consumer_data, -1);
1d4b027a
DG
1301 goto error;
1302 }
9363801e 1303 consumer_data->metadata_sock.fd_ptr = &consumer_data->metadata_fd;
331744e3
JD
1304 /* Create metadata socket lock. */
1305 consumer_data->metadata_sock.lock = zmalloc(sizeof(pthread_mutex_t));
1306 if (consumer_data->metadata_sock.lock == NULL) {
1307 PERROR("zmalloc pthread mutex");
1308 ret = -1;
1309 goto error;
1310 }
1311 pthread_mutex_init(consumer_data->metadata_sock.lock, NULL);
1312
a23ec3a7 1313 signal_consumer_condition(consumer_data, 1);
331744e3
JD
1314 DBG("Consumer command socket ready (fd: %d", consumer_data->cmd_sock);
1315 DBG("Consumer metadata socket ready (fd: %d)",
4ce514c4 1316 consumer_data->metadata_fd);
1d4b027a 1317 } else {
3bd1e081 1318 ERR("consumer error when waiting for SOCK_READY : %s",
1d4b027a
DG
1319 lttcomm_get_readable_code(-code));
1320 goto error;
1321 }
1322
331744e3 1323 /* Remove the consumerd error sock since we've established a connexion */
3bd1e081 1324 ret = lttng_poll_del(&events, consumer_data->err_sock);
72079cae 1325 if (ret < 0) {
72079cae
DG
1326 goto error;
1327 }
1328
331744e3 1329 /* Add new accepted error socket. */
5eb91c98
DG
1330 ret = lttng_poll_add(&events, sock, LPOLLIN | LPOLLRDHUP);
1331 if (ret < 0) {
72079cae 1332 goto error;
5eb91c98
DG
1333 }
1334
331744e3 1335 /* Add metadata socket that is successfully connected. */
4ce514c4 1336 ret = lttng_poll_add(&events, consumer_data->metadata_fd,
331744e3
JD
1337 LPOLLIN | LPOLLRDHUP);
1338 if (ret < 0) {
1339 goto error;
1340 }
1341
840cb59c 1342 health_code_update();
44a5e5eb 1343
331744e3 1344 /* Infinite blocking call, waiting for transmission */
88f2b785 1345restart_poll:
331744e3 1346 while (1) {
42fc1d0b
DG
1347 health_code_update();
1348
1349 /* Exit the thread because the thread quit pipe has been triggered. */
1350 if (should_quit) {
1351 /* Not a health error. */
1352 err = 0;
1353 goto exit;
1354 }
1355
331744e3
JD
1356 health_poll_entry();
1357 ret = lttng_poll_wait(&events, -1);
1358 health_poll_exit();
1359 if (ret < 0) {
1360 /*
1361 * Restart interrupted system call.
1362 */
1363 if (errno == EINTR) {
1364 goto restart_poll;
1365 }
1366 goto error;
88f2b785 1367 }
72079cae 1368
331744e3 1369 nb_fd = ret;
0d9c5d77 1370
331744e3
JD
1371 for (i = 0; i < nb_fd; i++) {
1372 /* Fetch once the poll data */
1373 revents = LTTNG_POLL_GETEV(&events, i);
1374 pollfd = LTTNG_POLL_GETFD(&events, i);
5eb91c98 1375
331744e3 1376 health_code_update();
44a5e5eb 1377
fd20dac9
MD
1378 if (!revents) {
1379 /* No activity for this FD (poll implementation). */
1380 continue;
1381 }
1382
42fc1d0b
DG
1383 /*
1384 * Thread quit pipe has been triggered, flag that we should stop
1385 * but continue the current loop to handle potential data from
1386 * consumer.
1387 */
1388 should_quit = sessiond_check_thread_quit_pipe(pollfd, revents);
5eb91c98 1389
331744e3
JD
1390 if (pollfd == sock) {
1391 /* Event on the consumerd socket */
1392 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1393 ERR("consumer err socket second poll error");
1394 goto error;
1395 }
1396 health_code_update();
1397 /* Wait for any kconsumerd error */
1398 ret = lttcomm_recv_unix_sock(sock, &code,
1399 sizeof(enum lttcomm_return_code));
1400 if (ret <= 0) {
1401 ERR("consumer closed the command socket");
1402 goto error;
1403 }
1404
1405 ERR("consumer return code : %s",
1406 lttcomm_get_readable_code(-code));
1407
1408 goto exit;
4ce514c4 1409 } else if (pollfd == consumer_data->metadata_fd) {
331744e3
JD
1410 /* UST metadata requests */
1411 ret = ust_consumer_metadata_request(
1412 &consumer_data->metadata_sock);
1413 if (ret < 0) {
1414 ERR("Handling metadata request");
1415 goto error;
1416 }
5eb91c98 1417 }
42fc1d0b 1418 /* No need for an else branch all FDs are tested prior. */
5eb91c98 1419 }
331744e3 1420 health_code_update();
5eb91c98
DG
1421 }
1422
139ac872 1423exit:
1d4b027a 1424error:
fdadac08
DG
1425 /*
1426 * We lock here because we are about to close the sockets and some other
92db7cdc
DG
1427 * thread might be using them so get exclusive access which will abort all
1428 * other consumer command by other threads.
fdadac08
DG
1429 */
1430 pthread_mutex_lock(&consumer_data->lock);
1431
5c827ce0
DG
1432 /* Immediately set the consumerd state to stopped */
1433 if (consumer_data->type == LTTNG_CONSUMER_KERNEL) {
1434 uatomic_set(&kernel_consumerd_state, CONSUMER_ERROR);
1435 } else if (consumer_data->type == LTTNG_CONSUMER64_UST ||
1436 consumer_data->type == LTTNG_CONSUMER32_UST) {
1437 uatomic_set(&ust_consumerd_state, CONSUMER_ERROR);
1438 } else {
1439 /* Code flow error... */
1440 assert(0);
1441 }
1442
76d7553f
MD
1443 if (consumer_data->err_sock >= 0) {
1444 ret = close(consumer_data->err_sock);
1445 if (ret) {
1446 PERROR("close");
1447 }
a76cbd9f 1448 consumer_data->err_sock = -1;
76d7553f
MD
1449 }
1450 if (consumer_data->cmd_sock >= 0) {
1451 ret = close(consumer_data->cmd_sock);
1452 if (ret) {
1453 PERROR("close");
1454 }
a76cbd9f 1455 consumer_data->cmd_sock = -1;
76d7553f 1456 }
96544455
SS
1457 if (consumer_data->metadata_sock.fd_ptr &&
1458 *consumer_data->metadata_sock.fd_ptr >= 0) {
9363801e 1459 ret = close(*consumer_data->metadata_sock.fd_ptr);
331744e3
JD
1460 if (ret) {
1461 PERROR("close");
1462 }
1463 }
76d7553f
MD
1464 if (sock >= 0) {
1465 ret = close(sock);
1466 if (ret) {
1467 PERROR("close");
1468 }
1469 }
273ea72c 1470
3bd1e081
MD
1471 unlink(consumer_data->err_unix_sock_path);
1472 unlink(consumer_data->cmd_unix_sock_path);
1473 consumer_data->pid = 0;
fdadac08 1474 pthread_mutex_unlock(&consumer_data->lock);
92db7cdc 1475
fdadac08 1476 /* Cleanup metadata socket mutex. */
96544455
SS
1477 if (consumer_data->metadata_sock.lock) {
1478 pthread_mutex_destroy(consumer_data->metadata_sock.lock);
1479 free(consumer_data->metadata_sock.lock);
1480 }
5eb91c98 1481 lttng_poll_clean(&events);
76d7553f 1482error_poll:
139ac872 1483 if (err) {
840cb59c 1484 health_error();
139ac872
MD
1485 ERR("Health error occurred in %s", __func__);
1486 }
8782cc74 1487 health_unregister(health_sessiond);
76d7553f 1488 DBG("consumer thread cleanup completed");
0177d773 1489
5eb91c98 1490 return NULL;
099e26bd
DG
1491}
1492
099e26bd
DG
1493/*
1494 * This thread manage application communication.
1d4b027a
DG
1495 */
1496static void *thread_manage_apps(void *data)
099e26bd 1497{
139ac872 1498 int i, ret, pollfd, err = -1;
6cd525e8 1499 ssize_t size_ret;
5eb91c98 1500 uint32_t revents, nb_fd;
5eb91c98 1501 struct lttng_poll_event events;
099e26bd
DG
1502
1503 DBG("[thread] Manage application started");
1504
f6a9efaa
DG
1505 rcu_register_thread();
1506 rcu_thread_online();
1507
6c71277b 1508 health_register(health_sessiond, HEALTH_SESSIOND_TYPE_APP_MANAGE);
927ca06a 1509
e547b070 1510 if (testpoint(sessiond_thread_manage_apps)) {
6993eeb3
CB
1511 goto error_testpoint;
1512 }
1513
840cb59c 1514 health_code_update();
44a5e5eb 1515
d0b96690 1516 ret = sessiond_set_thread_pollset(&events, 2);
5eb91c98 1517 if (ret < 0) {
76d7553f 1518 goto error_poll_create;
5eb91c98 1519 }
099e26bd 1520
5eb91c98
DG
1521 ret = lttng_poll_add(&events, apps_cmd_pipe[0], LPOLLIN | LPOLLRDHUP);
1522 if (ret < 0) {
1523 goto error;
1524 }
099e26bd 1525
e547b070 1526 if (testpoint(sessiond_thread_manage_apps_before_loop)) {
6993eeb3
CB
1527 goto error;
1528 }
8ac94142 1529
840cb59c 1530 health_code_update();
44a5e5eb 1531
5eb91c98 1532 while (1) {
7fa2082e 1533 DBG("Apps thread polling");
099e26bd
DG
1534
1535 /* Inifinite blocking call, waiting for transmission */
88f2b785 1536 restart:
a78af745 1537 health_poll_entry();
5eb91c98 1538 ret = lttng_poll_wait(&events, -1);
7fa2082e
MD
1539 DBG("Apps thread return from poll on %d fds",
1540 LTTNG_POLL_GETNB(&events));
a78af745 1541 health_poll_exit();
099e26bd 1542 if (ret < 0) {
88f2b785
MD
1543 /*
1544 * Restart interrupted system call.
1545 */
1546 if (errno == EINTR) {
1547 goto restart;
1548 }
099e26bd
DG
1549 goto error;
1550 }
1551
0d9c5d77
DG
1552 nb_fd = ret;
1553
5eb91c98
DG
1554 for (i = 0; i < nb_fd; i++) {
1555 /* Fetch once the poll data */
1556 revents = LTTNG_POLL_GETEV(&events, i);
1557 pollfd = LTTNG_POLL_GETFD(&events, i);
1558
840cb59c 1559 health_code_update();
44a5e5eb 1560
fd20dac9
MD
1561 if (!revents) {
1562 /* No activity for this FD (poll implementation). */
1563 continue;
1564 }
1565
5eb91c98 1566 /* Thread quit pipe has been closed. Killing thread. */
d0b96690 1567 ret = sessiond_check_thread_quit_pipe(pollfd, revents);
5eb91c98 1568 if (ret) {
139ac872
MD
1569 err = 0;
1570 goto exit;
5eb91c98 1571 }
099e26bd 1572
5eb91c98
DG
1573 /* Inspect the apps cmd pipe */
1574 if (pollfd == apps_cmd_pipe[0]) {
1575 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1576 ERR("Apps command pipe error");
0177d773 1577 goto error;
5eb91c98 1578 } else if (revents & LPOLLIN) {
d0b96690
DG
1579 int sock;
1580
5eb91c98 1581 /* Empty pipe */
6cd525e8
MD
1582 size_ret = lttng_read(apps_cmd_pipe[0], &sock, sizeof(sock));
1583 if (size_ret < sizeof(sock)) {
76d7553f 1584 PERROR("read apps cmd pipe");
5eb91c98
DG
1585 goto error;
1586 }
099e26bd 1587
840cb59c 1588 health_code_update();
44a5e5eb 1589
ffe60014 1590 /*
d0b96690
DG
1591 * We only monitor the error events of the socket. This
1592 * thread does not handle any incoming data from UST
1593 * (POLLIN).
ffe60014 1594 */
d0b96690
DG
1595 ret = lttng_poll_add(&events, sock,
1596 LPOLLERR | LPOLLHUP | LPOLLRDHUP);
1597 if (ret < 0) {
5eb91c98 1598 goto error;
e0c7ec2b 1599 }
acc7b41b 1600
d0b96690 1601 DBG("Apps with sock %d added to poll set", sock);
0177d773 1602 }
5eb91c98
DG
1603 } else {
1604 /*
54d01ffb
DG
1605 * At this point, we know that a registered application made
1606 * the event at poll_wait.
5eb91c98
DG
1607 */
1608 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
1609 /* Removing from the poll set */
1610 ret = lttng_poll_del(&events, pollfd);
1611 if (ret < 0) {
1612 goto error;
1613 }
099e26bd 1614
b9d9b220 1615 /* Socket closed on remote end. */
56fff090 1616 ust_app_unregister(pollfd);
5eb91c98 1617 }
099e26bd 1618 }
44a5e5eb 1619
840cb59c 1620 health_code_update();
099e26bd 1621 }
099e26bd
DG
1622 }
1623
139ac872 1624exit:
099e26bd 1625error:
5eb91c98 1626 lttng_poll_clean(&events);
76d7553f 1627error_poll_create:
6993eeb3 1628error_testpoint:
6620da75
DG
1629 utils_close_pipe(apps_cmd_pipe);
1630 apps_cmd_pipe[0] = apps_cmd_pipe[1] = -1;
1631
1632 /*
1633 * We don't clean the UST app hash table here since already registered
1634 * applications can still be controlled so let them be until the session
1635 * daemon dies or the applications stop.
1636 */
1637
139ac872 1638 if (err) {
840cb59c 1639 health_error();
139ac872
MD
1640 ERR("Health error occurred in %s", __func__);
1641 }
8782cc74 1642 health_unregister(health_sessiond);
76d7553f 1643 DBG("Application communication apps thread cleanup complete");
f6a9efaa
DG
1644 rcu_thread_offline();
1645 rcu_unregister_thread();
099e26bd
DG
1646 return NULL;
1647}
1648
d0b96690 1649/*
d88aee68
DG
1650 * Send a socket to a thread This is called from the dispatch UST registration
1651 * thread once all sockets are set for the application.
d0b96690 1652 *
b85dc84c
DG
1653 * The sock value can be invalid, we don't really care, the thread will handle
1654 * it and make the necessary cleanup if so.
1655 *
d0b96690
DG
1656 * On success, return 0 else a negative value being the errno message of the
1657 * write().
1658 */
d88aee68 1659static int send_socket_to_thread(int fd, int sock)
d0b96690 1660{
6cd525e8 1661 ssize_t ret;
d0b96690 1662
b85dc84c
DG
1663 /*
1664 * It's possible that the FD is set as invalid with -1 concurrently just
1665 * before calling this function being a shutdown state of the thread.
1666 */
1667 if (fd < 0) {
1668 ret = -EBADF;
1669 goto error;
1670 }
d0b96690 1671
6cd525e8
MD
1672 ret = lttng_write(fd, &sock, sizeof(sock));
1673 if (ret < sizeof(sock)) {
d88aee68 1674 PERROR("write apps pipe %d", fd);
d0b96690
DG
1675 if (ret < 0) {
1676 ret = -errno;
1677 }
1678 goto error;
1679 }
1680
1681 /* All good. Don't send back the write positive ret value. */
1682 ret = 0;
1683error:
6cd525e8 1684 return (int) ret;
d0b96690
DG
1685}
1686
f45e313d
DG
1687/*
1688 * Sanitize the wait queue of the dispatch registration thread meaning removing
1689 * invalid nodes from it. This is to avoid memory leaks for the case the UST
1690 * notify socket is never received.
1691 */
1692static void sanitize_wait_queue(struct ust_reg_wait_queue *wait_queue)
1693{
1694 int ret, nb_fd = 0, i;
1695 unsigned int fd_added = 0;
1696 struct lttng_poll_event events;
1697 struct ust_reg_wait_node *wait_node = NULL, *tmp_wait_node;
1698
1699 assert(wait_queue);
1700
1701 lttng_poll_init(&events);
1702
1703 /* Just skip everything for an empty queue. */
1704 if (!wait_queue->count) {
1705 goto end;
1706 }
1707
1708 ret = lttng_poll_create(&events, wait_queue->count, LTTNG_CLOEXEC);
1709 if (ret < 0) {
1710 goto error_create;
1711 }
1712
1713 cds_list_for_each_entry_safe(wait_node, tmp_wait_node,
1714 &wait_queue->head, head) {
1715 assert(wait_node->app);
1716 ret = lttng_poll_add(&events, wait_node->app->sock,
1717 LPOLLHUP | LPOLLERR);
1718 if (ret < 0) {
1719 goto error;
1720 }
1721
1722 fd_added = 1;
1723 }
1724
1725 if (!fd_added) {
1726 goto end;
1727 }
1728
1729 /*
1730 * Poll but don't block so we can quickly identify the faulty events and
1731 * clean them afterwards from the wait queue.
1732 */
1733 ret = lttng_poll_wait(&events, 0);
1734 if (ret < 0) {
1735 goto error;
1736 }
1737 nb_fd = ret;
1738
1739 for (i = 0; i < nb_fd; i++) {
1740 /* Get faulty FD. */
1741 uint32_t revents = LTTNG_POLL_GETEV(&events, i);
1742 int pollfd = LTTNG_POLL_GETFD(&events, i);
1743
fd20dac9
MD
1744 if (!revents) {
1745 /* No activity for this FD (poll implementation). */
1746 continue;
1747 }
1748
f45e313d
DG
1749 cds_list_for_each_entry_safe(wait_node, tmp_wait_node,
1750 &wait_queue->head, head) {
1751 if (pollfd == wait_node->app->sock &&
1752 (revents & (LPOLLHUP | LPOLLERR))) {
1753 cds_list_del(&wait_node->head);
1754 wait_queue->count--;
1755 ust_app_destroy(wait_node->app);
1756 free(wait_node);
1757 break;
1758 }
1759 }
1760 }
1761
1762 if (nb_fd > 0) {
1763 DBG("Wait queue sanitized, %d node were cleaned up", nb_fd);
1764 }
1765
1766end:
1767 lttng_poll_clean(&events);
1768 return;
1769
1770error:
1771 lttng_poll_clean(&events);
1772error_create:
1773 ERR("Unable to sanitize wait queue");
1774 return;
1775}
1776
099e26bd
DG
1777/*
1778 * Dispatch request from the registration threads to the application
1779 * communication thread.
1780 */
1781static void *thread_dispatch_ust_registration(void *data)
1782{
12e2b881 1783 int ret, err = -1;
8bdee6e2 1784 struct cds_wfcq_node *node;
099e26bd 1785 struct ust_command *ust_cmd = NULL;
f45e313d
DG
1786 struct ust_reg_wait_node *wait_node = NULL, *tmp_wait_node;
1787 struct ust_reg_wait_queue wait_queue = {
1788 .count = 0,
1789 };
d0b96690 1790
6c71277b 1791 health_register(health_sessiond, HEALTH_SESSIOND_TYPE_APP_REG_DISPATCH);
12e2b881 1792
9ad42ec1
MD
1793 if (testpoint(sessiond_thread_app_reg_dispatch)) {
1794 goto error_testpoint;
1795 }
1796
12e2b881
MD
1797 health_code_update();
1798
f45e313d 1799 CDS_INIT_LIST_HEAD(&wait_queue.head);
099e26bd
DG
1800
1801 DBG("[thread] Dispatch UST command started");
1802
26c9d55e 1803 while (!CMM_LOAD_SHARED(dispatch_thread_exit)) {
12e2b881
MD
1804 health_code_update();
1805
099e26bd
DG
1806 /* Atomically prepare the queue futex */
1807 futex_nto1_prepare(&ust_cmd_queue.futex);
1808
1809 do {
d0b96690 1810 struct ust_app *app = NULL;
7972aab2 1811 ust_cmd = NULL;
d0b96690 1812
f45e313d
DG
1813 /*
1814 * Make sure we don't have node(s) that have hung up before receiving
1815 * the notify socket. This is to clean the list in order to avoid
1816 * memory leaks from notify socket that are never seen.
1817 */
1818 sanitize_wait_queue(&wait_queue);
1819
12e2b881 1820 health_code_update();
099e26bd 1821 /* Dequeue command for registration */
8bdee6e2 1822 node = cds_wfcq_dequeue_blocking(&ust_cmd_queue.head, &ust_cmd_queue.tail);
099e26bd 1823 if (node == NULL) {
00a17c97 1824 DBG("Woken up but nothing in the UST command queue");
099e26bd
DG
1825 /* Continue thread execution */
1826 break;
1827 }
1828
1829 ust_cmd = caa_container_of(node, struct ust_command, node);
1830
2f50c8a3
DG
1831 DBG("Dispatching UST registration pid:%d ppid:%d uid:%d"
1832 " gid:%d sock:%d name:%s (version %d.%d)",
1833 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
1834 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
1835 ust_cmd->sock, ust_cmd->reg_msg.name,
1836 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
d0b96690
DG
1837
1838 if (ust_cmd->reg_msg.type == USTCTL_SOCKET_CMD) {
1839 wait_node = zmalloc(sizeof(*wait_node));
1840 if (!wait_node) {
1841 PERROR("zmalloc wait_node dispatch");
020d7f60
DG
1842 ret = close(ust_cmd->sock);
1843 if (ret < 0) {
1844 PERROR("close ust sock dispatch %d", ust_cmd->sock);
1845 }
51dec90d 1846 lttng_fd_put(LTTNG_FD_APPS, 1);
7972aab2 1847 free(ust_cmd);
d0b96690
DG
1848 goto error;
1849 }
1850 CDS_INIT_LIST_HEAD(&wait_node->head);
1851
1852 /* Create application object if socket is CMD. */
1853 wait_node->app = ust_app_create(&ust_cmd->reg_msg,
1854 ust_cmd->sock);
1855 if (!wait_node->app) {
1856 ret = close(ust_cmd->sock);
1857 if (ret < 0) {
1858 PERROR("close ust sock dispatch %d", ust_cmd->sock);
6620da75 1859 }
51dec90d 1860 lttng_fd_put(LTTNG_FD_APPS, 1);
d88aee68 1861 free(wait_node);
7972aab2 1862 free(ust_cmd);
d0b96690
DG
1863 continue;
1864 }
1865 /*
1866 * Add application to the wait queue so we can set the notify
1867 * socket before putting this object in the global ht.
1868 */
f45e313d
DG
1869 cds_list_add(&wait_node->head, &wait_queue.head);
1870 wait_queue.count++;
d0b96690 1871
7972aab2 1872 free(ust_cmd);
d0b96690
DG
1873 /*
1874 * We have to continue here since we don't have the notify
1875 * socket and the application MUST be added to the hash table
1876 * only at that moment.
1877 */
1878 continue;
1879 } else {
1880 /*
1881 * Look for the application in the local wait queue and set the
1882 * notify socket if found.
1883 */
d88aee68 1884 cds_list_for_each_entry_safe(wait_node, tmp_wait_node,
f45e313d 1885 &wait_queue.head, head) {
12e2b881 1886 health_code_update();
d0b96690
DG
1887 if (wait_node->app->pid == ust_cmd->reg_msg.pid) {
1888 wait_node->app->notify_sock = ust_cmd->sock;
1889 cds_list_del(&wait_node->head);
f45e313d 1890 wait_queue.count--;
d0b96690
DG
1891 app = wait_node->app;
1892 free(wait_node);
1893 DBG3("UST app notify socket %d is set", ust_cmd->sock);
1894 break;
1895 }
1896 }
020d7f60
DG
1897
1898 /*
1899 * With no application at this stage the received socket is
1900 * basically useless so close it before we free the cmd data
1901 * structure for good.
1902 */
1903 if (!app) {
1904 ret = close(ust_cmd->sock);
1905 if (ret < 0) {
1906 PERROR("close ust sock dispatch %d", ust_cmd->sock);
1907 }
51dec90d 1908 lttng_fd_put(LTTNG_FD_APPS, 1);
020d7f60 1909 }
7972aab2 1910 free(ust_cmd);
d0b96690
DG
1911 }
1912
1913 if (app) {
d0b96690
DG
1914 /*
1915 * @session_lock_list
1916 *
1917 * Lock the global session list so from the register up to the
1918 * registration done message, no thread can see the application
1919 * and change its state.
1920 */
1921 session_lock_list();
1922 rcu_read_lock();
d88aee68 1923
d0b96690
DG
1924 /*
1925 * Add application to the global hash table. This needs to be
1926 * done before the update to the UST registry can locate the
1927 * application.
1928 */
1929 ust_app_add(app);
d88aee68
DG
1930
1931 /* Set app version. This call will print an error if needed. */
1932 (void) ust_app_version(app);
1933
1934 /* Send notify socket through the notify pipe. */
1935 ret = send_socket_to_thread(apps_cmd_notify_pipe[1],
1936 app->notify_sock);
1937 if (ret < 0) {
1938 rcu_read_unlock();
1939 session_unlock_list();
b85dc84c
DG
1940 /*
1941 * No notify thread, stop the UST tracing. However, this is
1942 * not an internal error of the this thread thus setting
1943 * the health error code to a normal exit.
1944 */
1945 err = 0;
d88aee68 1946 goto error;
6620da75 1947 }
d88aee68 1948
d0b96690
DG
1949 /*
1950 * Update newly registered application with the tracing
1951 * registry info already enabled information.
1952 */
1953 update_ust_app(app->sock);
d88aee68
DG
1954
1955 /*
1956 * Don't care about return value. Let the manage apps threads
1957 * handle app unregistration upon socket close.
1958 */
1959 (void) ust_app_register_done(app->sock);
1960
1961 /*
1962 * Even if the application socket has been closed, send the app
1963 * to the thread and unregistration will take place at that
1964 * place.
1965 */
1966 ret = send_socket_to_thread(apps_cmd_pipe[1], app->sock);
d0b96690 1967 if (ret < 0) {
d88aee68
DG
1968 rcu_read_unlock();
1969 session_unlock_list();
b85dc84c
DG
1970 /*
1971 * No apps. thread, stop the UST tracing. However, this is
1972 * not an internal error of the this thread thus setting
1973 * the health error code to a normal exit.
1974 */
1975 err = 0;
d88aee68 1976 goto error;
d0b96690 1977 }
d88aee68 1978
d0b96690
DG
1979 rcu_read_unlock();
1980 session_unlock_list();
099e26bd 1981 }
099e26bd
DG
1982 } while (node != NULL);
1983
12e2b881 1984 health_poll_entry();
099e26bd
DG
1985 /* Futex wait on queue. Blocking call on futex() */
1986 futex_nto1_wait(&ust_cmd_queue.futex);
12e2b881 1987 health_poll_exit();
099e26bd 1988 }
12e2b881
MD
1989 /* Normal exit, no error */
1990 err = 0;
099e26bd
DG
1991
1992error:
d88aee68
DG
1993 /* Clean up wait queue. */
1994 cds_list_for_each_entry_safe(wait_node, tmp_wait_node,
f45e313d 1995 &wait_queue.head, head) {
d88aee68 1996 cds_list_del(&wait_node->head);
f45e313d 1997 wait_queue.count--;
d88aee68
DG
1998 free(wait_node);
1999 }
2000
9ad42ec1 2001error_testpoint:
099e26bd 2002 DBG("Dispatch thread dying");
12e2b881
MD
2003 if (err) {
2004 health_error();
2005 ERR("Health error occurred in %s", __func__);
2006 }
8782cc74 2007 health_unregister(health_sessiond);
099e26bd
DG
2008 return NULL;
2009}
2010
2011/*
2012 * This thread manage application registration.
2013 */
2014static void *thread_registration_apps(void *data)
1d4b027a 2015{
139ac872 2016 int sock = -1, i, ret, pollfd, err = -1;
5eb91c98
DG
2017 uint32_t revents, nb_fd;
2018 struct lttng_poll_event events;
099e26bd
DG
2019 /*
2020 * Get allocated in this thread, enqueued to a global queue, dequeued and
2021 * freed in the manage apps thread.
2022 */
2023 struct ust_command *ust_cmd = NULL;
1d4b027a 2024
099e26bd 2025 DBG("[thread] Manage application registration started");
1d4b027a 2026
6c71277b 2027 health_register(health_sessiond, HEALTH_SESSIOND_TYPE_APP_REG);
927ca06a 2028
e547b070 2029 if (testpoint(sessiond_thread_registration_apps)) {
6993eeb3
CB
2030 goto error_testpoint;
2031 }
8ac94142 2032
1d4b027a
DG
2033 ret = lttcomm_listen_unix_sock(apps_sock);
2034 if (ret < 0) {
76d7553f 2035 goto error_listen;
1d4b027a
DG
2036 }
2037
5eb91c98
DG
2038 /*
2039 * Pass 2 as size here for the thread quit pipe and apps socket. Nothing
2040 * more will be added to this poll set.
2041 */
d0b96690 2042 ret = sessiond_set_thread_pollset(&events, 2);
5eb91c98 2043 if (ret < 0) {
76d7553f 2044 goto error_create_poll;
5eb91c98 2045 }
273ea72c 2046
5eb91c98
DG
2047 /* Add the application registration socket */
2048 ret = lttng_poll_add(&events, apps_sock, LPOLLIN | LPOLLRDHUP);
2049 if (ret < 0) {
76d7553f 2050 goto error_poll_add;
5eb91c98 2051 }
273ea72c 2052
1d4b027a 2053 /* Notify all applications to register */
0fdd1e2c
DG
2054 ret = notify_ust_apps(1);
2055 if (ret < 0) {
2056 ERR("Failed to notify applications or create the wait shared memory.\n"
54d01ffb
DG
2057 "Execution continues but there might be problem for already\n"
2058 "running applications that wishes to register.");
0fdd1e2c 2059 }
1d4b027a
DG
2060
2061 while (1) {
2062 DBG("Accepting application registration");
273ea72c
DG
2063
2064 /* Inifinite blocking call, waiting for transmission */
88f2b785 2065 restart:
a78af745 2066 health_poll_entry();
5eb91c98 2067 ret = lttng_poll_wait(&events, -1);
a78af745 2068 health_poll_exit();
273ea72c 2069 if (ret < 0) {
88f2b785
MD
2070 /*
2071 * Restart interrupted system call.
2072 */
2073 if (errno == EINTR) {
2074 goto restart;
2075 }
273ea72c
DG
2076 goto error;
2077 }
2078
0d9c5d77
DG
2079 nb_fd = ret;
2080
5eb91c98 2081 for (i = 0; i < nb_fd; i++) {
840cb59c 2082 health_code_update();
139ac872 2083
5eb91c98
DG
2084 /* Fetch once the poll data */
2085 revents = LTTNG_POLL_GETEV(&events, i);
2086 pollfd = LTTNG_POLL_GETFD(&events, i);
273ea72c 2087
fd20dac9
MD
2088 if (!revents) {
2089 /* No activity for this FD (poll implementation). */
2090 continue;
2091 }
2092
5eb91c98 2093 /* Thread quit pipe has been closed. Killing thread. */
d0b96690 2094 ret = sessiond_check_thread_quit_pipe(pollfd, revents);
5eb91c98 2095 if (ret) {
139ac872
MD
2096 err = 0;
2097 goto exit;
90014c57 2098 }
1d4b027a 2099
5eb91c98
DG
2100 /* Event on the registration socket */
2101 if (pollfd == apps_sock) {
2102 if (revents & (LPOLLERR | LPOLLHUP | LPOLLRDHUP)) {
2103 ERR("Register apps socket poll error");
2104 goto error;
2105 } else if (revents & LPOLLIN) {
2106 sock = lttcomm_accept_unix_sock(apps_sock);
2107 if (sock < 0) {
2108 goto error;
2109 }
099e26bd 2110
16c5c8fa
DG
2111 /*
2112 * Set socket timeout for both receiving and ending.
2113 * app_socket_timeout is in seconds, whereas
2114 * lttcomm_setsockopt_rcv_timeout and
2115 * lttcomm_setsockopt_snd_timeout expect msec as
2116 * parameter.
2117 */
2118 (void) lttcomm_setsockopt_rcv_timeout(sock,
2119 app_socket_timeout * 1000);
2120 (void) lttcomm_setsockopt_snd_timeout(sock,
2121 app_socket_timeout * 1000);
2122
b662582b
DG
2123 /*
2124 * Set the CLOEXEC flag. Return code is useless because
2125 * either way, the show must go on.
2126 */
2127 (void) utils_set_fd_cloexec(sock);
2128
5eb91c98 2129 /* Create UST registration command for enqueuing */
ba7f0ae5 2130 ust_cmd = zmalloc(sizeof(struct ust_command));
5eb91c98 2131 if (ust_cmd == NULL) {
76d7553f 2132 PERROR("ust command zmalloc");
5eb91c98
DG
2133 goto error;
2134 }
1d4b027a 2135
5eb91c98
DG
2136 /*
2137 * Using message-based transmissions to ensure we don't
2138 * have to deal with partially received messages.
2139 */
4063050c
MD
2140 ret = lttng_fd_get(LTTNG_FD_APPS, 1);
2141 if (ret < 0) {
2142 ERR("Exhausted file descriptors allowed for applications.");
2143 free(ust_cmd);
2144 ret = close(sock);
2145 if (ret) {
2146 PERROR("close");
2147 }
2148 sock = -1;
2149 continue;
2150 }
d88aee68 2151
840cb59c 2152 health_code_update();
d0b96690
DG
2153 ret = ust_app_recv_registration(sock, &ust_cmd->reg_msg);
2154 if (ret < 0) {
5eb91c98 2155 free(ust_cmd);
d0b96690 2156 /* Close socket of the application. */
76d7553f
MD
2157 ret = close(sock);
2158 if (ret) {
2159 PERROR("close");
2160 }
4063050c 2161 lttng_fd_put(LTTNG_FD_APPS, 1);
76d7553f 2162 sock = -1;
5eb91c98
DG
2163 continue;
2164 }
840cb59c 2165 health_code_update();
099e26bd 2166
5eb91c98 2167 ust_cmd->sock = sock;
34a2494f 2168 sock = -1;
099e26bd 2169
5eb91c98
DG
2170 DBG("UST registration received with pid:%d ppid:%d uid:%d"
2171 " gid:%d sock:%d name:%s (version %d.%d)",
2172 ust_cmd->reg_msg.pid, ust_cmd->reg_msg.ppid,
2173 ust_cmd->reg_msg.uid, ust_cmd->reg_msg.gid,
2174 ust_cmd->sock, ust_cmd->reg_msg.name,
2175 ust_cmd->reg_msg.major, ust_cmd->reg_msg.minor);
54d01ffb 2176
5eb91c98
DG
2177 /*
2178 * Lock free enqueue the registration request. The red pill
54d01ffb 2179 * has been taken! This apps will be part of the *system*.
5eb91c98 2180 */
8bdee6e2 2181 cds_wfcq_enqueue(&ust_cmd_queue.head, &ust_cmd_queue.tail, &ust_cmd->node);
5eb91c98
DG
2182
2183 /*
2184 * Wake the registration queue futex. Implicit memory
8bdee6e2 2185 * barrier with the exchange in cds_wfcq_enqueue.
5eb91c98
DG
2186 */
2187 futex_nto1_wake(&ust_cmd_queue.futex);
2188 }
2189 }
90014c57 2190 }
1d4b027a
DG
2191 }
2192
139ac872 2193exit:
1d4b027a 2194error:
0fdd1e2c
DG
2195 /* Notify that the registration thread is gone */
2196 notify_ust_apps(0);
2197
a4b35e07 2198 if (apps_sock >= 0) {
76d7553f
MD
2199 ret = close(apps_sock);
2200 if (ret) {
2201 PERROR("close");
2202 }
a4b35e07 2203 }
46c3f085 2204 if (sock >= 0) {
76d7553f
MD
2205 ret = close(sock);
2206 if (ret) {
2207 PERROR("close");
2208 }
4063050c 2209 lttng_fd_put(LTTNG_FD_APPS, 1);
a4b35e07 2210 }
273ea72c 2211 unlink(apps_unix_sock_path);
0fdd1e2c 2212
76d7553f 2213error_poll_add:
5eb91c98 2214 lttng_poll_clean(&events);
76d7553f
MD
2215error_listen:
2216error_create_poll:
6993eeb3 2217error_testpoint:
76d7553f 2218 DBG("UST Registration thread cleanup complete");
9ad42ec1
MD
2219 if (err) {
2220 health_error();
2221 ERR("Health error occurred in %s", __func__);
2222 }
8782cc74 2223 health_unregister(health_sessiond);
5eb91c98 2224
1d4b027a
DG
2225 return NULL;
2226}
2227
8c0faa1d 2228/*
3bd1e081 2229 * Start the thread_manage_consumer. This must be done after a lttng-consumerd
d063d709 2230 * exec or it will fails.
8c0faa1d 2231 */
3bd1e081 2232static int spawn_consumer_thread(struct consumer_data *consumer_data)
8c0faa1d 2233{
a23ec3a7 2234 int ret, clock_ret;
ee0b0061
DG
2235 struct timespec timeout;
2236
a23ec3a7
DG
2237 /* Make sure we set the readiness flag to 0 because we are NOT ready */
2238 consumer_data->consumer_thread_is_ready = 0;
8c0faa1d 2239
a23ec3a7
DG
2240 /* Setup pthread condition */
2241 ret = pthread_condattr_init(&consumer_data->condattr);
4a15001e 2242 if (ret) {
a23ec3a7
DG
2243 errno = ret;
2244 PERROR("pthread_condattr_init consumer data");
2245 goto error;
2246 }
2247
2248 /*
2249 * Set the monotonic clock in order to make sure we DO NOT jump in time
2250 * between the clock_gettime() call and the timedwait call. See bug #324
2251 * for a more details and how we noticed it.
2252 */
2253 ret = pthread_condattr_setclock(&consumer_data->condattr, CLOCK_MONOTONIC);
4a15001e 2254 if (ret) {
a23ec3a7
DG
2255 errno = ret;
2256 PERROR("pthread_condattr_setclock consumer data");
ee0b0061
DG
2257 goto error;
2258 }
8c0faa1d 2259
a23ec3a7 2260 ret = pthread_cond_init(&consumer_data->cond, &consumer_data->condattr);
4a15001e 2261 if (ret) {
a23ec3a7
DG
2262 errno = ret;
2263 PERROR("pthread_cond_init consumer data");
2264 goto error;
2265 }
2266
2267 ret = pthread_create(&consumer_data->thread, NULL, thread_manage_consumer,
2268 consumer_data);
4a15001e
MD
2269 if (ret) {
2270 errno = ret;
3bd1e081 2271 PERROR("pthread_create consumer");
ee0b0061 2272 ret = -1;
8c0faa1d
DG
2273 goto error;
2274 }
2275
a23ec3a7
DG
2276 /* We are about to wait on a pthread condition */
2277 pthread_mutex_lock(&consumer_data->cond_mutex);
2278
ee0b0061 2279 /* Get time for sem_timedwait absolute timeout */
a23ec3a7
DG
2280 clock_ret = clock_gettime(CLOCK_MONOTONIC, &timeout);
2281 /*
2282 * Set the timeout for the condition timed wait even if the clock gettime
2283 * call fails since we might loop on that call and we want to avoid to
2284 * increment the timeout too many times.
2285 */
2286 timeout.tv_sec += DEFAULT_SEM_WAIT_TIMEOUT;
2287
2288 /*
2289 * The following loop COULD be skipped in some conditions so this is why we
2290 * set ret to 0 in order to make sure at least one round of the loop is
2291 * done.
2292 */
2293 ret = 0;
2294
2295 /*
2296 * Loop until the condition is reached or when a timeout is reached. Note
2297 * that the pthread_cond_timedwait(P) man page specifies that EINTR can NOT
2298 * be returned but the pthread_cond(3), from the glibc-doc, says that it is
2299 * possible. This loop does not take any chances and works with both of
2300 * them.
2301 */
2302 while (!consumer_data->consumer_thread_is_ready && ret != ETIMEDOUT) {
2303 if (clock_ret < 0) {
2304 PERROR("clock_gettime spawn consumer");
2305 /* Infinite wait for the consumerd thread to be ready */
2306 ret = pthread_cond_wait(&consumer_data->cond,
2307 &consumer_data->cond_mutex);
2308 } else {
2309 ret = pthread_cond_timedwait(&consumer_data->cond,
2310 &consumer_data->cond_mutex, &timeout);
2311 }
ee0b0061 2312 }
8c0faa1d 2313
a23ec3a7
DG
2314 /* Release the pthread condition */
2315 pthread_mutex_unlock(&consumer_data->cond_mutex);
2316
2317 if (ret != 0) {
2318 errno = ret;
2319 if (ret == ETIMEDOUT) {
4282f9a3
DG
2320 int pth_ret;
2321
ee0b0061
DG
2322 /*
2323 * Call has timed out so we kill the kconsumerd_thread and return
2324 * an error.
2325 */
a23ec3a7
DG
2326 ERR("Condition timed out. The consumer thread was never ready."
2327 " Killing it");
4282f9a3
DG
2328 pth_ret = pthread_cancel(consumer_data->thread);
2329 if (pth_ret < 0) {
3bd1e081 2330 PERROR("pthread_cancel consumer thread");
ee0b0061
DG
2331 }
2332 } else {
a23ec3a7 2333 PERROR("pthread_cond_wait failed consumer thread");
ee0b0061 2334 }
4282f9a3
DG
2335 /* Caller is expecting a negative value on failure. */
2336 ret = -1;
ee0b0061
DG
2337 goto error;
2338 }
2339
3bd1e081
MD
2340 pthread_mutex_lock(&consumer_data->pid_mutex);
2341 if (consumer_data->pid == 0) {
a23ec3a7 2342 ERR("Consumerd did not start");
3bd1e081 2343 pthread_mutex_unlock(&consumer_data->pid_mutex);
712ea556
DG
2344 goto error;
2345 }
3bd1e081 2346 pthread_mutex_unlock(&consumer_data->pid_mutex);
712ea556 2347
8c0faa1d
DG
2348 return 0;
2349
2350error:
2351 return ret;
2352}
2353
d9800920 2354/*
3bd1e081 2355 * Join consumer thread
d9800920 2356 */
3bd1e081 2357static int join_consumer_thread(struct consumer_data *consumer_data)
cf3af59e
MD
2358{
2359 void *status;
cf3af59e 2360
e8209f6b
DG
2361 /* Consumer pid must be a real one. */
2362 if (consumer_data->pid > 0) {
c617c0c6 2363 int ret;
3bd1e081 2364 ret = kill(consumer_data->pid, SIGTERM);
cf3af59e 2365 if (ret) {
4a15001e 2366 PERROR("Error killing consumer daemon");
cf3af59e
MD
2367 return ret;
2368 }
3bd1e081 2369 return pthread_join(consumer_data->thread, &status);
cf3af59e
MD
2370 } else {
2371 return 0;
2372 }
2373}
2374
8c0faa1d 2375/*
3bd1e081 2376 * Fork and exec a consumer daemon (consumerd).
8c0faa1d 2377 *
d063d709 2378 * Return pid if successful else -1.
8c0faa1d 2379 */
3bd1e081 2380static pid_t spawn_consumerd(struct consumer_data *consumer_data)
8c0faa1d
DG
2381{
2382 int ret;
2383 pid_t pid;
94c55f17 2384 const char *consumer_to_use;
53086306 2385 const char *verbosity;
94c55f17 2386 struct stat st;
8c0faa1d 2387
3bd1e081 2388 DBG("Spawning consumerd");
c49dc785 2389
8c0faa1d
DG
2390 pid = fork();
2391 if (pid == 0) {
2392 /*
3bd1e081 2393 * Exec consumerd.
8c0faa1d 2394 */
daee5345 2395 if (opt_verbose_consumer) {
53086306 2396 verbosity = "--verbose";
4421f712 2397 } else if (lttng_opt_quiet) {
53086306 2398 verbosity = "--quiet";
4421f712
DG
2399 } else {
2400 verbosity = "";
53086306 2401 }
4421f712 2402
3bd1e081
MD
2403 switch (consumer_data->type) {
2404 case LTTNG_CONSUMER_KERNEL:
94c55f17 2405 /*
c7704d57
DG
2406 * Find out which consumerd to execute. We will first try the
2407 * 64-bit path, then the sessiond's installation directory, and
2408 * fallback on the 32-bit one,
94c55f17 2409 */
63a799e8
AM
2410 DBG3("Looking for a kernel consumer at these locations:");
2411 DBG3(" 1) %s", consumerd64_bin);
2412 DBG3(" 2) %s/%s", INSTALL_BIN_PATH, CONSUMERD_FILE);
2413 DBG3(" 3) %s", consumerd32_bin);
94c55f17 2414 if (stat(consumerd64_bin, &st) == 0) {
63a799e8 2415 DBG3("Found location #1");
94c55f17 2416 consumer_to_use = consumerd64_bin;
94c55f17 2417 } else if (stat(INSTALL_BIN_PATH "/" CONSUMERD_FILE, &st) == 0) {
63a799e8 2418 DBG3("Found location #2");
94c55f17 2419 consumer_to_use = INSTALL_BIN_PATH "/" CONSUMERD_FILE;
eb1e0bd4 2420 } else if (stat(consumerd32_bin, &st) == 0) {
63a799e8 2421 DBG3("Found location #3");
eb1e0bd4 2422 consumer_to_use = consumerd32_bin;
94c55f17 2423 } else {
63a799e8 2424 DBG("Could not find any valid consumerd executable");
4282f9a3 2425 ret = -EINVAL;
94c55f17
AM
2426 break;
2427 }
2428 DBG("Using kernel consumer at: %s", consumer_to_use);
4282f9a3 2429 ret = execl(consumer_to_use,
94c55f17
AM
2430 "lttng-consumerd", verbosity, "-k",
2431 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
2432 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
6c71277b 2433 "--group", tracing_group_name,
94c55f17 2434 NULL);
3bd1e081 2435 break;
7753dea8
MD
2436 case LTTNG_CONSUMER64_UST:
2437 {
b1e0b6b6 2438 char *tmpnew = NULL;
8f4905da
MD
2439
2440 if (consumerd64_libdir[0] != '\0') {
2441 char *tmp;
2442 size_t tmplen;
2443
e8fa9fb0 2444 tmp = lttng_secure_getenv("LD_LIBRARY_PATH");
8f4905da
MD
2445 if (!tmp) {
2446 tmp = "";
2447 }
2448 tmplen = strlen("LD_LIBRARY_PATH=")
2449 + strlen(consumerd64_libdir) + 1 /* : */ + strlen(tmp);
2450 tmpnew = zmalloc(tmplen + 1 /* \0 */);
2451 if (!tmpnew) {
2452 ret = -ENOMEM;
2453 goto error;
2454 }
2455 strcpy(tmpnew, "LD_LIBRARY_PATH=");
2456 strcat(tmpnew, consumerd64_libdir);
2457 if (tmp[0] != '\0') {
2458 strcat(tmpnew, ":");
2459 strcat(tmpnew, tmp);
2460 }
2461 ret = putenv(tmpnew);
2462 if (ret) {
2463 ret = -errno;
c6f76da9 2464 free(tmpnew);
8f4905da
MD
2465 goto error;
2466 }
2467 }
94c55f17 2468 DBG("Using 64-bit UST consumer at: %s", consumerd64_bin);
a5a6aff3 2469 ret = execl(consumerd64_bin, "lttng-consumerd", verbosity, "-u",
7753dea8
MD
2470 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
2471 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
6c71277b 2472 "--group", tracing_group_name,
7753dea8 2473 NULL);
8f4905da
MD
2474 if (consumerd64_libdir[0] != '\0') {
2475 free(tmpnew);
2476 }
3bd1e081 2477 break;
7753dea8
MD
2478 }
2479 case LTTNG_CONSUMER32_UST:
2480 {
937dde8e 2481 char *tmpnew = NULL;
8f4905da
MD
2482
2483 if (consumerd32_libdir[0] != '\0') {
2484 char *tmp;
2485 size_t tmplen;
2486
e8fa9fb0 2487 tmp = lttng_secure_getenv("LD_LIBRARY_PATH");
8f4905da
MD
2488 if (!tmp) {
2489 tmp = "";
2490 }
2491 tmplen = strlen("LD_LIBRARY_PATH=")
2492 + strlen(consumerd32_libdir) + 1 /* : */ + strlen(tmp);
2493 tmpnew = zmalloc(tmplen + 1 /* \0 */);
2494 if (!tmpnew) {
2495 ret = -ENOMEM;
2496 goto error;
2497 }
2498 strcpy(tmpnew, "LD_LIBRARY_PATH=");
2499 strcat(tmpnew, consumerd32_libdir);
2500 if (tmp[0] != '\0') {
2501 strcat(tmpnew, ":");
2502 strcat(tmpnew, tmp);
2503 }
2504 ret = putenv(tmpnew);
2505 if (ret) {
2506 ret = -errno;
c6f76da9 2507 free(tmpnew);
8f4905da
MD
2508 goto error;
2509 }
2510 }
94c55f17 2511 DBG("Using 32-bit UST consumer at: %s", consumerd32_bin);
a5a6aff3 2512 ret = execl(consumerd32_bin, "lttng-consumerd", verbosity, "-u",
7753dea8
MD
2513 "--consumerd-cmd-sock", consumer_data->cmd_unix_sock_path,
2514 "--consumerd-err-sock", consumer_data->err_unix_sock_path,
6c71277b 2515 "--group", tracing_group_name,
7753dea8 2516 NULL);
8f4905da
MD
2517 if (consumerd32_libdir[0] != '\0') {
2518 free(tmpnew);
2519 }
7753dea8
MD
2520 break;
2521 }
3bd1e081 2522 default:
76d7553f 2523 PERROR("unknown consumer type");
3bd1e081
MD
2524 exit(EXIT_FAILURE);
2525 }
8c0faa1d 2526 if (errno != 0) {
4282f9a3 2527 PERROR("Consumer execl()");
8c0faa1d 2528 }
4282f9a3 2529 /* Reaching this point, we got a failure on our execl(). */
8c0faa1d
DG
2530 exit(EXIT_FAILURE);
2531 } else if (pid > 0) {
2532 ret = pid;
8c0faa1d 2533 } else {
76d7553f 2534 PERROR("start consumer fork");
8c0faa1d 2535 ret = -errno;
8c0faa1d 2536 }
8f4905da 2537error:
8c0faa1d
DG
2538 return ret;
2539}
2540
693bd40b 2541/*
3bd1e081 2542 * Spawn the consumerd daemon and session daemon thread.
693bd40b 2543 */
3bd1e081 2544static int start_consumerd(struct consumer_data *consumer_data)
693bd40b 2545{
c617c0c6 2546 int ret;
edb8b045
DG
2547
2548 /*
2549 * Set the listen() state on the socket since there is a possible race
2550 * between the exec() of the consumer daemon and this call if place in the
2551 * consumer thread. See bug #366 for more details.
2552 */
2553 ret = lttcomm_listen_unix_sock(consumer_data->err_sock);
2554 if (ret < 0) {
2555 goto error;
2556 }
693bd40b 2557
3bd1e081
MD
2558 pthread_mutex_lock(&consumer_data->pid_mutex);
2559 if (consumer_data->pid != 0) {
2560 pthread_mutex_unlock(&consumer_data->pid_mutex);
c49dc785
DG
2561 goto end;
2562 }
693bd40b 2563
3bd1e081 2564 ret = spawn_consumerd(consumer_data);
c49dc785 2565 if (ret < 0) {
3bd1e081
MD
2566 ERR("Spawning consumerd failed");
2567 pthread_mutex_unlock(&consumer_data->pid_mutex);
c49dc785 2568 goto error;
693bd40b 2569 }
c49dc785 2570
3bd1e081
MD
2571 /* Setting up the consumer_data pid */
2572 consumer_data->pid = ret;
48842b30 2573 DBG2("Consumer pid %d", consumer_data->pid);
3bd1e081 2574 pthread_mutex_unlock(&consumer_data->pid_mutex);
693bd40b 2575
3bd1e081
MD
2576 DBG2("Spawning consumer control thread");
2577 ret = spawn_consumer_thread(consumer_data);
693bd40b 2578 if (ret < 0) {
3bd1e081 2579 ERR("Fatal error spawning consumer control thread");
693bd40b
DG
2580 goto error;
2581 }
2582
c49dc785 2583end:
693bd40b
DG
2584 return 0;
2585
2586error:
331744e3 2587 /* Cleanup already created sockets on error. */
edb8b045 2588 if (consumer_data->err_sock >= 0) {
c617c0c6
MD
2589 int err;
2590
edb8b045
DG
2591 err = close(consumer_data->err_sock);
2592 if (err < 0) {
2593 PERROR("close consumer data error socket");
2594 }
2595 }
693bd40b
DG
2596 return ret;
2597}
2598
b73401da 2599/*
096102bd 2600 * Setup necessary data for kernel tracer action.
b73401da 2601 */
096102bd 2602static int init_kernel_tracer(void)
b73401da
DG
2603{
2604 int ret;
b73401da 2605
096102bd
DG
2606 /* Modprobe lttng kernel modules */
2607 ret = modprobe_lttng_control();
b73401da 2608 if (ret < 0) {
b73401da
DG
2609 goto error;
2610 }
2611
096102bd
DG
2612 /* Open debugfs lttng */
2613 kernel_tracer_fd = open(module_proc_lttng, O_RDWR);
2614 if (kernel_tracer_fd < 0) {
2615 DBG("Failed to open %s", module_proc_lttng);
2f77fc4b
DG
2616 ret = -1;
2617 goto error_open;
54d01ffb
DG
2618 }
2619
2f77fc4b
DG
2620 /* Validate kernel version */
2621 ret = kernel_validate_version(kernel_tracer_fd);
2622 if (ret < 0) {
2623 goto error_version;
b551a063 2624 }
54d01ffb 2625
2f77fc4b
DG
2626 ret = modprobe_lttng_data();
2627 if (ret < 0) {
2628 goto error_modules;
54d01ffb
DG
2629 }
2630
2f77fc4b
DG
2631 DBG("Kernel tracer fd %d", kernel_tracer_fd);
2632 return 0;
2633
2634error_version:
2635 modprobe_remove_lttng_control();
2636 ret = close(kernel_tracer_fd);
2637 if (ret) {
2638 PERROR("close");
b551a063 2639 }
2f77fc4b 2640 kernel_tracer_fd = -1;
f73fabfd 2641 return LTTNG_ERR_KERN_VERSION;
b551a063 2642
2f77fc4b
DG
2643error_modules:
2644 ret = close(kernel_tracer_fd);
2645 if (ret) {
2646 PERROR("close");
b551a063 2647 }
54d01ffb 2648
2f77fc4b
DG
2649error_open:
2650 modprobe_remove_lttng_control();
54d01ffb
DG
2651
2652error:
2f77fc4b
DG
2653 WARN("No kernel tracer available");
2654 kernel_tracer_fd = -1;
2655 if (!is_root) {
f73fabfd 2656 return LTTNG_ERR_NEED_ROOT_SESSIOND;
2f77fc4b 2657 } else {
f73fabfd 2658 return LTTNG_ERR_KERN_NA;
2f77fc4b 2659 }
54d01ffb
DG
2660}
2661
2f77fc4b 2662
54d01ffb 2663/*
2f77fc4b
DG
2664 * Copy consumer output from the tracing session to the domain session. The
2665 * function also applies the right modification on a per domain basis for the
2666 * trace files destination directory.
36b588ed
MD
2667 *
2668 * Should *NOT* be called with RCU read-side lock held.
54d01ffb 2669 */
2f77fc4b 2670static int copy_session_consumer(int domain, struct ltt_session *session)
54d01ffb
DG
2671{
2672 int ret;
2f77fc4b
DG
2673 const char *dir_name;
2674 struct consumer_output *consumer;
2675
2676 assert(session);
2677 assert(session->consumer);
54d01ffb 2678
b551a063
DG
2679 switch (domain) {
2680 case LTTNG_DOMAIN_KERNEL:
2f77fc4b 2681 DBG3("Copying tracing session consumer output in kernel session");
09a90bcd
DG
2682 /*
2683 * XXX: We should audit the session creation and what this function
2684 * does "extra" in order to avoid a destroy since this function is used
2685 * in the domain session creation (kernel and ust) only. Same for UST
2686 * domain.
2687 */
2688 if (session->kernel_session->consumer) {
2689 consumer_destroy_output(session->kernel_session->consumer);
2690 }
2f77fc4b
DG
2691 session->kernel_session->consumer =
2692 consumer_copy_output(session->consumer);
2693 /* Ease our life a bit for the next part */
2694 consumer = session->kernel_session->consumer;
2695 dir_name = DEFAULT_KERNEL_TRACE_DIR;
b551a063 2696 break;
f20baf8e 2697 case LTTNG_DOMAIN_JUL:
5cdb6027 2698 case LTTNG_DOMAIN_LOG4J:
0e115563 2699 case LTTNG_DOMAIN_PYTHON:
b551a063 2700 case LTTNG_DOMAIN_UST:
2f77fc4b 2701 DBG3("Copying tracing session consumer output in UST session");
09a90bcd
DG
2702 if (session->ust_session->consumer) {
2703 consumer_destroy_output(session->ust_session->consumer);
2704 }
2f77fc4b
DG
2705 session->ust_session->consumer =
2706 consumer_copy_output(session->consumer);
2707 /* Ease our life a bit for the next part */
2708 consumer = session->ust_session->consumer;
2709 dir_name = DEFAULT_UST_TRACE_DIR;
b551a063
DG
2710 break;
2711 default:
f73fabfd 2712 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
54d01ffb
DG
2713 goto error;
2714 }
2715
2f77fc4b 2716 /* Append correct directory to subdir */
c30ce0b3
CB
2717 strncat(consumer->subdir, dir_name,
2718 sizeof(consumer->subdir) - strlen(consumer->subdir) - 1);
2f77fc4b
DG
2719 DBG3("Copy session consumer subdir %s", consumer->subdir);
2720
f73fabfd 2721 ret = LTTNG_OK;
54d01ffb
DG
2722
2723error:
2724 return ret;
2725}
2726
00e2e675 2727/*
2f77fc4b 2728 * Create an UST session and add it to the session ust list.
36b588ed
MD
2729 *
2730 * Should *NOT* be called with RCU read-side lock held.
00e2e675 2731 */
2f77fc4b
DG
2732static int create_ust_session(struct ltt_session *session,
2733 struct lttng_domain *domain)
00e2e675
DG
2734{
2735 int ret;
2f77fc4b 2736 struct ltt_ust_session *lus = NULL;
00e2e675 2737
a4b92340 2738 assert(session);
2f77fc4b
DG
2739 assert(domain);
2740 assert(session->consumer);
a4b92340 2741
2f77fc4b 2742 switch (domain->type) {
f20baf8e 2743 case LTTNG_DOMAIN_JUL:
5cdb6027 2744 case LTTNG_DOMAIN_LOG4J:
0e115563 2745 case LTTNG_DOMAIN_PYTHON:
2f77fc4b
DG
2746 case LTTNG_DOMAIN_UST:
2747 break;
2748 default:
2749 ERR("Unknown UST domain on create session %d", domain->type);
f73fabfd 2750 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
00e2e675
DG
2751 goto error;
2752 }
2753
2f77fc4b
DG
2754 DBG("Creating UST session");
2755
dec56f6c 2756 lus = trace_ust_create_session(session->id);
2f77fc4b 2757 if (lus == NULL) {
f73fabfd 2758 ret = LTTNG_ERR_UST_SESS_FAIL;
a4b92340
DG
2759 goto error;
2760 }
2761
2f77fc4b
DG
2762 lus->uid = session->uid;
2763 lus->gid = session->gid;
2bba9e53 2764 lus->output_traces = session->output_traces;
27babd3a 2765 lus->snapshot_mode = session->snapshot_mode;
ecc48a90 2766 lus->live_timer_interval = session->live_timer;
2f77fc4b 2767 session->ust_session = lus;
d7ba1388 2768 if (session->shm_path[0]) {
3d071855
MD
2769 strncpy(lus->root_shm_path, session->shm_path,
2770 sizeof(lus->root_shm_path));
2771 lus->root_shm_path[sizeof(lus->root_shm_path) - 1] = '\0';
d7ba1388
MD
2772 strncpy(lus->shm_path, session->shm_path,
2773 sizeof(lus->shm_path));
2774 lus->shm_path[sizeof(lus->shm_path) - 1] = '\0';
2775 strncat(lus->shm_path, "/ust",
2776 sizeof(lus->shm_path) - strlen(lus->shm_path) - 1);
2777 }
2f77fc4b
DG
2778 /* Copy session output to the newly created UST session */
2779 ret = copy_session_consumer(domain->type, session);
f73fabfd 2780 if (ret != LTTNG_OK) {
00e2e675
DG
2781 goto error;
2782 }
2783
f73fabfd 2784 return LTTNG_OK;
00e2e675
DG
2785
2786error:
2f77fc4b
DG
2787 free(lus);
2788 session->ust_session = NULL;
00e2e675
DG
2789 return ret;
2790}
2791
2792/*
2f77fc4b 2793 * Create a kernel tracer session then create the default channel.
00e2e675 2794 */
2f77fc4b 2795static int create_kernel_session(struct ltt_session *session)
00e2e675
DG
2796{
2797 int ret;
a4b92340 2798
2f77fc4b 2799 DBG("Creating kernel session");
00e2e675 2800
2f77fc4b
DG
2801 ret = kernel_create_session(session, kernel_tracer_fd);
2802 if (ret < 0) {
f73fabfd 2803 ret = LTTNG_ERR_KERN_SESS_FAIL;
00e2e675
DG
2804 goto error;
2805 }
2806
2f77fc4b
DG
2807 /* Code flow safety */
2808 assert(session->kernel_session);
2809
2810 /* Copy session output to the newly created Kernel session */
2811 ret = copy_session_consumer(LTTNG_DOMAIN_KERNEL, session);
f73fabfd 2812 if (ret != LTTNG_OK) {
a4b92340
DG
2813 goto error;
2814 }
2815
2f77fc4b
DG
2816 /* Create directory(ies) on local filesystem. */
2817 if (session->kernel_session->consumer->type == CONSUMER_DST_LOCAL &&
2818 strlen(session->kernel_session->consumer->dst.trace_path) > 0) {
2819 ret = run_as_mkdir_recursive(
2820 session->kernel_session->consumer->dst.trace_path,
2821 S_IRWXU | S_IRWXG, session->uid, session->gid);
2822 if (ret < 0) {
2823 if (ret != -EEXIST) {
2824 ERR("Trace directory creation error");
00e2e675
DG
2825 goto error;
2826 }
00e2e675 2827 }
2f77fc4b 2828 }
00e2e675 2829
2f77fc4b
DG
2830 session->kernel_session->uid = session->uid;
2831 session->kernel_session->gid = session->gid;
2bba9e53 2832 session->kernel_session->output_traces = session->output_traces;
27babd3a 2833 session->kernel_session->snapshot_mode = session->snapshot_mode;
00e2e675 2834
f73fabfd 2835 return LTTNG_OK;
00e2e675 2836
2f77fc4b
DG
2837error:
2838 trace_kernel_destroy_session(session->kernel_session);
2839 session->kernel_session = NULL;
2840 return ret;
2841}
00e2e675 2842
2f77fc4b
DG
2843/*
2844 * Count number of session permitted by uid/gid.
2845 */
2846static unsigned int lttng_sessions_count(uid_t uid, gid_t gid)
2847{
2848 unsigned int i = 0;
2849 struct ltt_session *session;
07424f16 2850
2f77fc4b
DG
2851 DBG("Counting number of available session for UID %d GID %d",
2852 uid, gid);
2853 cds_list_for_each_entry(session, &session_list_ptr->head, list) {
00e2e675 2854 /*
2f77fc4b 2855 * Only list the sessions the user can control.
00e2e675 2856 */
2f77fc4b
DG
2857 if (!session_access_ok(session, uid, gid)) {
2858 continue;
2859 }
2860 i++;
a4b92340 2861 }
2f77fc4b 2862 return i;
00e2e675
DG
2863}
2864
54d01ffb
DG
2865/*
2866 * Process the command requested by the lttng client within the command
2867 * context structure. This function make sure that the return structure (llm)
2868 * is set and ready for transmission before returning.
2869 *
2870 * Return any error encountered or 0 for success.
53a80697
MD
2871 *
2872 * "sock" is only used for special-case var. len data.
36b588ed
MD
2873 *
2874 * Should *NOT* be called with RCU read-side lock held.
54d01ffb 2875 */
53a80697
MD
2876static int process_client_msg(struct command_ctx *cmd_ctx, int sock,
2877 int *sock_error)
54d01ffb 2878{
f73fabfd 2879 int ret = LTTNG_OK;
44d3bd01 2880 int need_tracing_session = 1;
2e09ba09 2881 int need_domain;
54d01ffb
DG
2882
2883 DBG("Processing client command %d", cmd_ctx->lsm->cmd_type);
2884
53a80697
MD
2885 *sock_error = 0;
2886
2e09ba09
MD
2887 switch (cmd_ctx->lsm->cmd_type) {
2888 case LTTNG_CREATE_SESSION:
27babd3a 2889 case LTTNG_CREATE_SESSION_SNAPSHOT:
ecc48a90 2890 case LTTNG_CREATE_SESSION_LIVE:
2e09ba09
MD
2891 case LTTNG_DESTROY_SESSION:
2892 case LTTNG_LIST_SESSIONS:
2893 case LTTNG_LIST_DOMAINS:
2894 case LTTNG_START_TRACE:
2895 case LTTNG_STOP_TRACE:
6d805429 2896 case LTTNG_DATA_PENDING:
da3c9ec1
DG
2897 case LTTNG_SNAPSHOT_ADD_OUTPUT:
2898 case LTTNG_SNAPSHOT_DEL_OUTPUT:
2899 case LTTNG_SNAPSHOT_LIST_OUTPUT:
2900 case LTTNG_SNAPSHOT_RECORD:
fb198a11 2901 case LTTNG_SAVE_SESSION:
d7ba1388 2902 case LTTNG_SET_SESSION_SHM_PATH:
2e09ba09 2903 need_domain = 0;
3aace903 2904 break;
2e09ba09
MD
2905 default:
2906 need_domain = 1;
2907 }
2908
2909 if (opt_no_kernel && need_domain
2910 && cmd_ctx->lsm->domain.type == LTTNG_DOMAIN_KERNEL) {
531d29f9 2911 if (!is_root) {
f73fabfd 2912 ret = LTTNG_ERR_NEED_ROOT_SESSIOND;
531d29f9 2913 } else {
f73fabfd 2914 ret = LTTNG_ERR_KERN_NA;
531d29f9 2915 }
4fba7219
DG
2916 goto error;
2917 }
2918
8d3113b2
DG
2919 /* Deny register consumer if we already have a spawned consumer. */
2920 if (cmd_ctx->lsm->cmd_type == LTTNG_REGISTER_CONSUMER) {
2921 pthread_mutex_lock(&kconsumer_data.pid_mutex);
2922 if (kconsumer_data.pid > 0) {
f73fabfd 2923 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
fa317f24 2924 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
8d3113b2
DG
2925 goto error;
2926 }
2927 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
2928 }
2929
54d01ffb
DG
2930 /*
2931 * Check for command that don't needs to allocate a returned payload. We do
44d3bd01 2932 * this here so we don't have to make the call for no payload at each
54d01ffb
DG
2933 * command.
2934 */
2935 switch(cmd_ctx->lsm->cmd_type) {
2936 case LTTNG_LIST_SESSIONS:
2937 case LTTNG_LIST_TRACEPOINTS:
f37d259d 2938 case LTTNG_LIST_TRACEPOINT_FIELDS:
54d01ffb
DG
2939 case LTTNG_LIST_DOMAINS:
2940 case LTTNG_LIST_CHANNELS:
2941 case LTTNG_LIST_EVENTS:
834978fd 2942 case LTTNG_LIST_SYSCALLS:
54d01ffb
DG
2943 break;
2944 default:
2945 /* Setup lttng message with no payload */
2946 ret = setup_lttng_msg(cmd_ctx, 0);
2947 if (ret < 0) {
2948 /* This label does not try to unlock the session */
2949 goto init_setup_error;
2950 }
2951 }
2952
2953 /* Commands that DO NOT need a session. */
2954 switch (cmd_ctx->lsm->cmd_type) {
54d01ffb 2955 case LTTNG_CREATE_SESSION:
27babd3a 2956 case LTTNG_CREATE_SESSION_SNAPSHOT:
ecc48a90 2957 case LTTNG_CREATE_SESSION_LIVE:
2e09ba09 2958 case LTTNG_CALIBRATE:
54d01ffb
DG
2959 case LTTNG_LIST_SESSIONS:
2960 case LTTNG_LIST_TRACEPOINTS:
834978fd 2961 case LTTNG_LIST_SYSCALLS:
f37d259d 2962 case LTTNG_LIST_TRACEPOINT_FIELDS:
fb198a11 2963 case LTTNG_SAVE_SESSION:
44d3bd01 2964 need_tracing_session = 0;
54d01ffb
DG
2965 break;
2966 default:
2967 DBG("Getting session %s by name", cmd_ctx->lsm->session.name);
256a5576
MD
2968 /*
2969 * We keep the session list lock across _all_ commands
2970 * for now, because the per-session lock does not
2971 * handle teardown properly.
2972 */
74babd95 2973 session_lock_list();
54d01ffb
DG
2974 cmd_ctx->session = session_find_by_name(cmd_ctx->lsm->session.name);
2975 if (cmd_ctx->session == NULL) {
bba2d65f 2976 ret = LTTNG_ERR_SESS_NOT_FOUND;
54d01ffb
DG
2977 goto error;
2978 } else {
2979 /* Acquire lock for the session */
2980 session_lock(cmd_ctx->session);
2981 }
2982 break;
2983 }
b389abbe 2984
5f3ecf22
DG
2985 /*
2986 * Commands that need a valid session but should NOT create one if none
2987 * exists. Instead of creating one and destroying it when the command is
2988 * handled, process that right before so we save some round trip in useless
2989 * code path.
2990 */
2991 switch (cmd_ctx->lsm->cmd_type) {
2992 case LTTNG_DISABLE_CHANNEL:
2993 case LTTNG_DISABLE_EVENT:
5f3ecf22
DG
2994 switch (cmd_ctx->lsm->domain.type) {
2995 case LTTNG_DOMAIN_KERNEL:
2996 if (!cmd_ctx->session->kernel_session) {
2997 ret = LTTNG_ERR_NO_CHANNEL;
2998 goto error;
2999 }
3000 break;
3001 case LTTNG_DOMAIN_JUL:
5cdb6027 3002 case LTTNG_DOMAIN_LOG4J:
0e115563 3003 case LTTNG_DOMAIN_PYTHON:
5f3ecf22
DG
3004 case LTTNG_DOMAIN_UST:
3005 if (!cmd_ctx->session->ust_session) {
3006 ret = LTTNG_ERR_NO_CHANNEL;
3007 goto error;
3008 }
3009 break;
3010 default:
3011 ret = LTTNG_ERR_UNKNOWN_DOMAIN;
3012 goto error;
3013 }
3014 default:
3015 break;
3016 }
3017
2e09ba09
MD
3018 if (!need_domain) {
3019 goto skip_domain;
3020 }
a4b92340 3021
54d01ffb
DG
3022 /*
3023 * Check domain type for specific "pre-action".
3024 */
3025 switch (cmd_ctx->lsm->domain.type) {
3026 case LTTNG_DOMAIN_KERNEL:
d1f1c568 3027 if (!is_root) {
f73fabfd 3028 ret = LTTNG_ERR_NEED_ROOT_SESSIOND;
d1f1c568
DG
3029 goto error;
3030 }
3031
54d01ffb 3032 /* Kernel tracer check */
a4b35e07 3033 if (kernel_tracer_fd == -1) {
54d01ffb 3034 /* Basically, load kernel tracer modules */
096102bd
DG
3035 ret = init_kernel_tracer();
3036 if (ret != 0) {
54d01ffb
DG
3037 goto error;
3038 }
3039 }
5eb91c98 3040
5c827ce0
DG
3041 /* Consumer is in an ERROR state. Report back to client */
3042 if (uatomic_read(&kernel_consumerd_state) == CONSUMER_ERROR) {
f73fabfd 3043 ret = LTTNG_ERR_NO_KERNCONSUMERD;
5c827ce0
DG
3044 goto error;
3045 }
3046
54d01ffb 3047 /* Need a session for kernel command */
44d3bd01 3048 if (need_tracing_session) {
54d01ffb 3049 if (cmd_ctx->session->kernel_session == NULL) {
6df2e2c9 3050 ret = create_kernel_session(cmd_ctx->session);
5eb91c98 3051 if (ret < 0) {
f73fabfd 3052 ret = LTTNG_ERR_KERN_SESS_FAIL;
5eb91c98
DG
3053 goto error;
3054 }
b389abbe 3055 }
7d29a247 3056
54d01ffb 3057 /* Start the kernel consumer daemon */
3bd1e081
MD
3058 pthread_mutex_lock(&kconsumer_data.pid_mutex);
3059 if (kconsumer_data.pid == 0 &&
785d2d0d 3060 cmd_ctx->lsm->cmd_type != LTTNG_REGISTER_CONSUMER) {
3bd1e081
MD
3061 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
3062 ret = start_consumerd(&kconsumer_data);
7d29a247 3063 if (ret < 0) {
f73fabfd 3064 ret = LTTNG_ERR_KERN_CONSUMER_FAIL;
54d01ffb 3065 goto error;
950131af 3066 }
5c827ce0 3067 uatomic_set(&kernel_consumerd_state, CONSUMER_STARTED);
3ff2ecac
MD
3068 } else {
3069 pthread_mutex_unlock(&kconsumer_data.pid_mutex);
33a2b854 3070 }
173af62f 3071
a4b92340
DG
3072 /*
3073 * The consumer was just spawned so we need to add the socket to
3074 * the consumer output of the session if exist.
3075 */
3076 ret = consumer_create_socket(&kconsumer_data,
3077 cmd_ctx->session->kernel_session->consumer);
3078 if (ret < 0) {
3079 goto error;
173af62f 3080 }
0d0c377a 3081 }
5c827ce0 3082
54d01ffb 3083 break;
b9dfb167 3084 case LTTNG_DOMAIN_JUL:
5cdb6027 3085 case LTTNG_DOMAIN_LOG4J:
0e115563 3086 case LTTNG_DOMAIN_PYTHON:
2bdd86d4 3087 case LTTNG_DOMAIN_UST:
44d3bd01 3088 {
b51ec5b4
MD
3089 if (!ust_app_supported()) {
3090 ret = LTTNG_ERR_NO_UST;
3091 goto error;
3092 }
5c827ce0
DG
3093 /* Consumer is in an ERROR state. Report back to client */
3094 if (uatomic_read(&ust_consumerd_state) == CONSUMER_ERROR) {
f73fabfd 3095 ret = LTTNG_ERR_NO_USTCONSUMERD;
5c827ce0
DG
3096 goto error;
3097 }
3098
44d3bd01 3099 if (need_tracing_session) {
a4b92340 3100 /* Create UST session if none exist. */
f6a9efaa 3101 if (cmd_ctx->session->ust_session == NULL) {